18664307547631 has 2 divisors, whose sum is σ = 18664307547632. Its totient is φ = 18664307547630.

The previous prime is 18664307547563. The next prime is 18664307547701. The reversal of 18664307547631 is 13674570346681.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-18664307547631 is a prime.

It is a super-2 number, since 2×18664307547631² (a number of 27 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18664307547631.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18664307548631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (31) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9332153773815 + 9332153773816.

It is an arithmetic number, because the mean of its divisors is an integer number (9332153773816).

Almost surely, 2^{18664307547631} is an apocalyptic number.

18664307547631 is a deficient number, since it is larger than the sum of its proper divisors (1).

18664307547631 is an equidigital number, since it uses as much as digits as its factorization.

18664307547631 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 60963840, while the sum is 61.

The spelling of 18664307547631 in words is "eighteen trillion, six hundred sixty-four billion, three hundred seven million, five hundred forty-seven thousand, six hundred thirty-one".