631432061661 has 4 divisors (see below), whose sum is σ = 841909415552. Its totient is φ = 420954707772.

The previous prime is 631432061639. The next prime is 631432061671. The reversal of 631432061661 is 166160234136.

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 631432061661 - 2⁹ = 631432061149 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 (631432061621) 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, 105238676941 + ... + 105238676946.

It is an arithmetic number, because the mean of its divisors is an integer number (210477353888).

Almost surely, 2^631432061661 is an apocalyptic number.

It is an amenable number.

631432061661 is a deficient number, since it is larger than the sum of its proper divisors (210477353891).

631432061661 is a wasteful number, since it uses less digits than its factorization.

631432061661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 210477353890.

The product of its (nonzero) digits is 93312, while the sum is 39.

Adding to 631432061661 its reverse (166160234136), we get a palindrome (797592295797).

The spelling of 631432061661 in words is "six hundred thirty-one billion, four hundred thirty-two million, sixty-one thousand, six hundred sixty-one".