16551621263 has 2 divisors, whose sum is σ = 16551621264. Its totient is φ = 16551621262.

The previous prime is 16551621257. The next prime is 16551621283. The reversal of 16551621263 is 36212615561.

It is a weak prime.

It is an emirp because it is prime and its reverse (36212615561) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16551621263 - 2⁸ = 16551621007 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16551621253) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8275810631 + 8275810632.

It is an arithmetic number, because the mean of its divisors is an integer number (8275810632).

Almost surely, 2^16551621263 is an apocalyptic number.

16551621263 is a deficient number, since it is larger than the sum of its proper divisors (1).

16551621263 is an equidigital number, since it uses as much as digits as its factorization.

16551621263 is an evil number, because the sum of its binary digits is even.

The product of its digits is 64800, while the sum is 38.

The spelling of 16551621263 in words is "sixteen billion, five hundred fifty-one million, six hundred twenty-one thousand, two hundred sixty-three".