155405431880 has 64 divisors (see below), whose sum is σ = 357547109040. Its totient is φ = 60768893952.

The previous prime is 155405431877. The next prime is 155405431931. The reversal of 155405431880 is 88134504551.

It can be written as a sum of positive squares in 8 ways, for example, as 110331594244 + 45073837636 = 332162^2 + 212306^2 .

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, 454922 + ... + 719558.

Almost surely, 2^155405431880 is an apocalyptic number.

155405431880 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 155405431880, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (178773554520).

155405431880 is an abundant number, since it is smaller than the sum of its proper divisors (202141677160).

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

155405431880 is a wasteful number, since it uses less digits than its factorization.

155405431880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 264978 (or 264974 counting only the distinct ones).

The product of its (nonzero) digits is 384000, while the sum is 44.

The spelling of 155405431880 in words is "one hundred fifty-five billion, four hundred five million, four hundred thirty-one thousand, eight hundred eighty".