631732398781 has 4 divisors (see below), whose sum is σ = 689162616864. Its totient is φ = 574302180700.

The previous prime is 631732398757. The next prime is 631732398823. The reversal of 631732398781 is 187893237136.

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 a cyclic number.

It is not a de Polignac number, because 631732398781 - 2¹³ = 631732390589 is a prime.

It is a super-2 number, since 2×631732398781² (a number of 24 digits) contains 22 as substring.

It is a pancake number, because a pancake can be divided into 631732398781 parts by 1124039 straight cuts.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (631732398701) 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, 28715109025 + ... + 28715109046.

It is an arithmetic number, because the mean of its divisors is an integer number (172290654216).

Almost surely, 2^631732398781 is an apocalyptic number.

631732398781 is the 355453-rd centered decagonal number.

It is an amenable number.

631732398781 is a deficient number, since it is larger than the sum of its proper divisors (57430218083).

631732398781 is a wasteful number, since it uses less digits than its factorization.

631732398781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57430218082.

The product of its digits is 9144576, while the sum is 58.

The spelling of 631732398781 in words is "six hundred thirty-one billion, seven hundred thirty-two million, three hundred ninety-eight thousand, seven hundred eighty-one".