155431320 has 64 divisors (see below), whose sum is σ = 508688640. Its totient is φ = 37680000.

The previous prime is 155431319. The next prime is 155431327. The reversal of 155431320 is 23134551.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155431327) 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, 57556 + ... + 60195.

It is an arithmetic number, because the mean of its divisors is an integer number (7948260).

Almost surely, 2^155431320 is an apocalyptic number.

155431320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

155431320 is an abundant number, since it is smaller than the sum of its proper divisors (353257320).

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

155431320 is a wasteful number, since it uses less digits than its factorization.

155431320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117776 (or 117772 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 24.

The square root of 155431320 is about 12467.2097920906. The cubic root of 155431320 is about 537.6663353961. Note that the first 3 decimals are identical.

Adding to 155431320 its reverse (23134551), we get a palindrome (178565871).

The spelling of 155431320 in words is "one hundred fifty-five million, four hundred thirty-one thousand, three hundred twenty".