663131387961 has 24 divisors (see below), whose sum is σ = 1094915600064. Its totient is φ = 378855197280.

The previous prime is 663131387959. The next prime is 663131387969. The reversal of 663131387961 is 169783131366.

It is not a de Polignac number, because 663131387961 - 2¹ = 663131387959 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 663131387898 and 663131387907.

It is not an unprimeable number, because it can be changed into a prime (663131387969) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 756666 + ... + 1377971.

It is an arithmetic number, because the mean of its divisors is an integer number (45621483336).

Almost surely, 2^663131387961 is an apocalyptic number.

It is an amenable number.

663131387961 is a deficient number, since it is larger than the sum of its proper divisors (431784212103).

663131387961 is a wasteful number, since it uses less digits than its factorization.

663131387961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2139581 (or 2139578 counting only the distinct ones).

The product of its digits is 2939328, while the sum is 54.

The spelling of 663131387961 in words is "six hundred sixty-three billion, one hundred thirty-one million, three hundred eighty-seven thousand, nine hundred sixty-one".