31655550661 has 4 divisors (see below), whose sum is σ = 36177772192. Its totient is φ = 27133329132.

The previous prime is 31655550659. The next prime is 31655550697. The reversal of 31655550661 is 16605555613.

It is a happy number.

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 not a de Polignac number, because 31655550661 - 2¹ = 31655550659 is a prime.

It is a super-2 number, since 2×31655550661² (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 (31655550631) 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, 2261110755 + ... + 2261110768.

It is an arithmetic number, because the mean of its divisors is an integer number (9044443048).

Almost surely, 2^31655550661 is an apocalyptic number.

It is an amenable number.

31655550661 is a deficient number, since it is larger than the sum of its proper divisors (4522221531).

31655550661 is an equidigital number, since it uses as much as digits as its factorization.

31655550661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4522221530.

The product of its (nonzero) digits is 405000, while the sum is 43.

The spelling of 31655550661 in words is "thirty-one billion, six hundred fifty-five million, five hundred fifty thousand, six hundred sixty-one".