631666733621 has 96 divisors (see below), whose sum is σ = 897101568000. Its totient is φ = 437603886720.

The previous prime is 631666733609. The next prime is 631666733623. The reversal of 631666733621 is 126337666136.

It is a happy number.

It is not a de Polignac number, because 631666733621 - 2¹⁰ = 631666732597 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 631666733621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (631666733623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 12458480 + ... + 12509078.

It is an arithmetic number, because the mean of its divisors is an integer number (9344808000).

Almost surely, 2^631666733621 is an apocalyptic number.

It is an amenable number.

631666733621 is a deficient number, since it is larger than the sum of its proper divisors (265434834379).

631666733621 is a wasteful number, since it uses less digits than its factorization.

631666733621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50719 (or 50712 counting only the distinct ones).

The product of its digits is 2939328, while the sum is 50.

The spelling of 631666733621 in words is "six hundred thirty-one billion, six hundred sixty-six million, seven hundred thirty-three thousand, six hundred twenty-one".