155555540 has 48 divisors (see below), whose sum is σ = 374976000. Its totient is φ = 53098752.

The previous prime is 155555539. The next prime is 155555549. The reversal of 155555540 is 45555551.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (35).

It is a self number, because there is not a number n which added to its sum of digits gives 155555540.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155555549) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31136 + ... + 35784.

It is an arithmetic number, because the mean of its divisors is an integer number (7812000).

Almost surely, 2^155555540 is an apocalyptic number.

155555540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 155555540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (187488000).

155555540 is an abundant number, since it is smaller than the sum of its proper divisors (219420460).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

155555540 is a wasteful number, since it uses less digits than its factorization.

155555540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4904 (or 4902 counting only the distinct ones).

The product of its (nonzero) digits is 62500, while the sum is 35.

The square root of 155555540 is about 12472.1906656369. The cubic root of 155555540 is about 537.8095307479.

155555540 divided by its sum of digits (35) gives a palindrome (4444444).

It can be divided in two parts, 15 and 5555540, that added together give a palindrome (5555555).

The spelling of 155555540 in words is "one hundred fifty-five million, five hundred fifty-five thousand, five hundred forty".