31897749993 has 8 divisors (see below), whose sum is σ = 44768772000. Its totient is φ = 20145947328.

The previous prime is 31897749953. The next prime is 31897750009. The reversal of 31897749993 is 39994779813.

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

It is not a de Polignac number, because 31897749993 - 2⁶ = 31897749929 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31897749943) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 279804768 + ... + 279804881.

It is an arithmetic number, because the mean of its divisors is an integer number (5596096500).

Almost surely, 2^31897749993 is an apocalyptic number.

It is an amenable number.

31897749993 is a deficient number, since it is larger than the sum of its proper divisors (12871022007).

31897749993 is a wasteful number, since it uses less digits than its factorization.

31897749993 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 559609671.

The product of its digits is 92588832, while the sum is 69.

The spelling of 31897749993 in words is "thirty-one billion, eight hundred ninety-seven million, seven hundred forty-nine thousand, nine hundred ninety-three".