31980865847 has 4 divisors (see below), whose sum is σ = 36549560976. Its totient is φ = 27412170720.

The previous prime is 31980865843. The next prime is 31980865883. The reversal of 31980865847 is 74856808913.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 74856808913 = 53 ⋅1412392621.

It is a cyclic number.

It is not a de Polignac number, because 31980865847 - 2² = 31980865843 is a prime.

It is a super-2 number, since 2×31980865847² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31980865841) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2284347554 + ... + 2284347567.

It is an arithmetic number, because the mean of its divisors is an integer number (9137390244).

Almost surely, 2^31980865847 is an apocalyptic number.

31980865847 is a deficient number, since it is larger than the sum of its proper divisors (4568695129).

31980865847 is an equidigital number, since it uses as much as digits as its factorization.

31980865847 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4568695128.

The product of its (nonzero) digits is 11612160, while the sum is 59.

The spelling of 31980865847 in words is "thirty-one billion, nine hundred eighty million, eight hundred sixty-five thousand, eight hundred forty-seven".