664581416951 has 2 divisors, whose sum is σ = 664581416952. Its totient is φ = 664581416950.

The previous prime is 664581416903. The next prime is 664581417041. The reversal of 664581416951 is 159614185466.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-664581416951 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (664581416351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332290708475 + 332290708476.

It is an arithmetic number, because the mean of its divisors is an integer number (332290708476).

Almost surely, 2^664581416951 is an apocalyptic number.

664581416951 is a deficient number, since it is larger than the sum of its proper divisors (1).

664581416951 is an equidigital number, since it uses as much as digits as its factorization.

664581416951 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6220800, while the sum is 56.

The spelling of 664581416951 in words is "six hundred sixty-four billion, five hundred eighty-one million, four hundred sixteen thousand, nine hundred fifty-one".