31680817481 has 4 divisors (see below), whose sum is σ = 33058244352. Its totient is φ = 30303390612.

The previous prime is 31680817459. The next prime is 31680817489. The reversal of 31680817481 is 18471808613.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 31680817481 - 2¹⁰ = 31680816457 is a prime.

It is a super-2 number, since 2×31680817481² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (31680817489) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 688713401 + ... + 688713446.

It is an arithmetic number, because the mean of its divisors is an integer number (8264561088).

Almost surely, 2^31680817481 is an apocalyptic number.

It is an amenable number.

31680817481 is a deficient number, since it is larger than the sum of its proper divisors (1377426871).

31680817481 is a wasteful number, since it uses less digits than its factorization.

31680817481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1377426870.

The product of its (nonzero) digits is 258048, while the sum is 47.

The spelling of 31680817481 in words is "thirty-one billion, six hundred eighty million, eight hundred seventeen thousand, four hundred eighty-one".