155520040 has 64 divisors (see below), whose sum is σ = 389869200. Its totient is φ = 55437312.

The previous prime is 155520017. The next prime is 155520067. The reversal of 155520040 is 40025551.

It can be written as a sum of positive squares in 8 ways, for example, as 34035556 + 121484484 = 5834^2 + 11022^2 .

It is a junction number, because it is equal to n+sod(n) for n = 155519993 and 155520020.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9924 + ... + 20236.

Almost surely, 2^155520040 is an apocalyptic number.

155520040 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 155520040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (194934600).

155520040 is an abundant number, since it is smaller than the sum of its proper divisors (234349160).

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

155520040 is a wasteful number, since it uses less digits than its factorization.

155520040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10366 (or 10362 counting only the distinct ones).

The product of its (nonzero) digits is 1000, while the sum is 22.

The square root of 155520040 is about 12470.7674182466. The cubic root of 155520040 is about 537.7686156918.

Adding to 155520040 its reverse (40025551), we get a palindrome (195545591).

The spelling of 155520040 in words is "one hundred fifty-five million, five hundred twenty thousand, forty".