18925216651 has 4 divisors (see below), whose sum is σ = 20645690904. Its totient is φ = 17204742400.

The previous prime is 18925216649. The next prime is 18925216657. The reversal of 18925216651 is 15661252981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15661252981 = 11 ⋅1423750271.

It is a cyclic number.

It is not a de Polignac number, because 18925216651 - 2¹ = 18925216649 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18925216657) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 860237110 + ... + 860237131.

It is an arithmetic number, because the mean of its divisors is an integer number (5161422726).

Almost surely, 2^18925216651 is an apocalyptic number.

18925216651 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

18925216651 is a deficient number, since it is larger than the sum of its proper divisors (1720474253).

18925216651 is a wasteful number, since it uses less digits than its factorization.

18925216651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1720474252.

The product of its digits is 259200, while the sum is 46.

The spelling of 18925216651 in words is "eighteen billion, nine hundred twenty-five million, two hundred sixteen thousand, six hundred fifty-one".