31920359986 has 4 divisors (see below), whose sum is σ = 47880539982. Its totient is φ = 15960179992.

The previous prime is 31920359971. The next prime is 31920359987. The reversal of 31920359986 is 68995302913.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 16121126961 + 15799233025 = 126969^2 + 125695^2 .

It is not an unprimeable number, because it can be changed into a prime (31920359987) 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 as a sum of consecutive naturals, namely, 7980089995 + ... + 7980089998.

Almost surely, 2^31920359986 is an apocalyptic number.

31920359986 is a deficient number, since it is larger than the sum of its proper divisors (15960179996).

31920359986 is a wasteful number, since it uses less digits than its factorization.

31920359986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15960179995.

The product of its (nonzero) digits is 3149280, while the sum is 55.

The spelling of 31920359986 in words is "thirty-one billion, nine hundred twenty million, three hundred fifty-nine thousand, nine hundred eighty-six".