31899720159 has 16 divisors (see below), whose sum is σ = 50038777440. Its totient is φ = 20015510400.

The previous prime is 31899720131. The next prime is 31899720169. The reversal of 31899720159 is 95102799813.

It is not a de Polignac number, because 31899720159 - 2¹² = 31899716063 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31899720109) 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, 34748692 + ... + 34749609.

It is an arithmetic number, because the mean of its divisors is an integer number (3127423590).

Almost surely, 2^31899720159 is an apocalyptic number.

31899720159 is a deficient number, since it is larger than the sum of its proper divisors (18139057281).

31899720159 is a wasteful number, since it uses less digits than its factorization.

31899720159 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69498327 (or 69498321 counting only the distinct ones).

The product of its (nonzero) digits is 1224720, while the sum is 54.

The spelling of 31899720159 in words is "thirty-one billion, eight hundred ninety-nine million, seven hundred twenty thousand, one hundred fifty-nine".