15663663451 has 2 divisors, whose sum is σ = 15663663452. Its totient is φ = 15663663450.

The previous prime is 15663663409. The next prime is 15663663461. The reversal of 15663663451 is 15436636651.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 15663663451 - 2²¹ = 15661566299 is a prime.

It is not a weakly prime, because it can be changed into another prime (15663663461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7831831725 + 7831831726.

It is an arithmetic number, because the mean of its divisors is an integer number (7831831726).

Almost surely, 2^15663663451 is an apocalyptic number.

15663663451 is a deficient number, since it is larger than the sum of its proper divisors (1).

15663663451 is an equidigital number, since it uses as much as digits as its factorization.

15663663451 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1166400, while the sum is 46.

The spelling of 15663663451 in words is "fifteen billion, six hundred sixty-three million, six hundred sixty-three thousand, four hundred fifty-one".