155640931 has 8 divisors (see below), whose sum is σ = 163987200. Its totient is φ = 147426312.

The previous prime is 155640917. The next prime is 155640937. The reversal of 155640931 is 139046551.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 155640931 - 2⁷ = 155640803 is a prime.

It is a super-2 number, since 2×155640931² = 48448198805093522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (155640937) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 30481 + ... + 35218.

It is an arithmetic number, because the mean of its divisors is an integer number (20498400).

Almost surely, 2^155640931 is an apocalyptic number.

155640931 is a deficient number, since it is larger than the sum of its proper divisors (8346269).

155640931 is a wasteful number, since it uses less digits than its factorization.

155640931 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65825.

The product of its (nonzero) digits is 16200, while the sum is 34.

The square root of 155640931 is about 12475.6134518508. The cubic root of 155640931 is about 537.9079215284.

It can be divided in two parts, 1556 and 40931, that multiplied together give a palindrome (63688636).

The spelling of 155640931 in words is "one hundred fifty-five million, six hundred forty thousand, nine hundred thirty-one".