31646685665 has 64 divisors (see below), whose sum is σ = 50476400640. Its totient is φ = 18507709440.

The previous prime is 31646685661. The next prime is 31646685683. The reversal of 31646685665 is 56658664613.

It is a happy number.

It is not a de Polignac number, because 31646685665 - 2² = 31646685661 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 31646685665.

It is not an unprimeable number, because it can be changed into a prime (31646685661) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 199160 + ... + 320870.

It is an arithmetic number, because the mean of its divisors is an integer number (788693760).

Almost surely, 2^31646685665 is an apocalyptic number.

31646685665 is a gapful number since it is divisible by the number (35) formed by its first and last digit.

It is an amenable number.

31646685665 is a deficient number, since it is larger than the sum of its proper divisors (18829714975).

31646685665 is a wasteful number, since it uses less digits than its factorization.

31646685665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 121782.

The product of its digits is 18662400, while the sum is 56.

The spelling of 31646685665 in words is "thirty-one billion, six hundred forty-six million, six hundred eighty-five thousand, six hundred sixty-five".