155901138720 has 96 divisors (see below), whose sum is σ = 491735059200. Its totient is φ = 41518909440.

The previous prime is 155901138719. The next prime is 155901138727. The reversal of 155901138720 is 27831109551.

It is a tau number, because it is divible by the number of its divisors (96).

It is not an unprimeable number, because it can be changed into a prime (155901138727) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 151881 + ... + 578679.

It is an arithmetic number, because the mean of its divisors is an integer number (5122240200).

Almost surely, 2^155901138720 is an apocalyptic number.

155901138720 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 155901138720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (245867529600).

155901138720 is an abundant number, since it is smaller than the sum of its proper divisors (335833920480).

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

155901138720 is a wasteful number, since it uses less digits than its factorization.

155901138720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 427578 (or 427570 counting only the distinct ones).

The product of its (nonzero) digits is 75600, while the sum is 42.

The spelling of 155901138720 in words is "one hundred fifty-five billion, nine hundred one million, one hundred thirty-eight thousand, seven hundred twenty".