31321385647 has 4 divisors (see below), whose sum is σ = 31446172296. Its totient is φ = 31196599000.

The previous prime is 31321385617. The next prime is 31321385653. The reversal of 31321385647 is 74658312313.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-31321385647 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31321385617) 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, 62392948 + ... + 62393449.

It is an arithmetic number, because the mean of its divisors is an integer number (7861543074).

Almost surely, 2^31321385647 is an apocalyptic number.

31321385647 is a deficient number, since it is larger than the sum of its proper divisors (124786649).

31321385647 is a wasteful number, since it uses less digits than its factorization.

31321385647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124786648.

The product of its digits is 362880, while the sum is 43.

The spelling of 31321385647 in words is "thirty-one billion, three hundred twenty-one million, three hundred eighty-five thousand, six hundred forty-seven".