16653621587 has 2 divisors, whose sum is σ = 16653621588. Its totient is φ = 16653621586.

The previous prime is 16653621541. The next prime is 16653621629. The reversal of 16653621587 is 78512635661.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-16653621587 is a prime.

It is a super-2 number, since 2×16653621587² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (16653621487) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8326810793 + 8326810794.

It is an arithmetic number, because the mean of its divisors is an integer number (8326810794).

Almost surely, 2^16653621587 is an apocalyptic number.

16653621587 is a deficient number, since it is larger than the sum of its proper divisors (1).

16653621587 is an equidigital number, since it uses as much as digits as its factorization.

16653621587 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1814400, while the sum is 50.

The spelling of 16653621587 in words is "sixteen billion, six hundred fifty-three million, six hundred twenty-one thousand, five hundred eighty-seven".