651691660641 has 32 divisors (see below), whose sum is σ = 1048262496000. Its totient is φ = 359554003200.

The previous prime is 651691660637. The next prime is 651691660651. The reversal of 651691660641 is 146066196156.

It is not a de Polignac number, because 651691660641 - 2² = 651691660637 is a prime.

It is not an unprimeable number, because it can be changed into a prime (651691660651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10889560 + ... + 10949241.

It is an arithmetic number, because the mean of its divisors is an integer number (32758203000).

Almost surely, 2^651691660641 is an apocalyptic number.

It is an amenable number.

651691660641 is a deficient number, since it is larger than the sum of its proper divisors (396570835359).

651691660641 is a wasteful number, since it uses less digits than its factorization.

651691660641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21838854 (or 21838840 counting only the distinct ones).

The product of its (nonzero) digits is 1399680, while the sum is 51.

The spelling of 651691660641 in words is "six hundred fifty-one billion, six hundred ninety-one million, six hundred sixty thousand, six hundred forty-one".