155645440 has 80 divisors (see below), whose sum is σ = 376480368. Its totient is φ = 61710336.

The previous prime is 155645437. The next prime is 155645449. The reversal of 155645440 is 44546551.

It is a tau number, because it is divible by the number of its divisors (80).

It is a junction number, because it is equal to n+sod(n) for n = 155645396 and 155645405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155645449) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 417094 + ... + 417466.

Almost surely, 2^155645440 is an apocalyptic number.

155645440 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 155645440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (188240184).

155645440 is an abundant number, since it is smaller than the sum of its proper divisors (220834928).

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

155645440 is an equidigital number, since it uses as much as digits as its factorization.

155645440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 559 (or 543 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 34.

The square root of 155645440 is about 12475.7941630984. The cubic root of 155645440 is about 537.9131159704.

The spelling of 155645440 in words is "one hundred fifty-five million, six hundred forty-five thousand, four hundred forty".