18916220879 has 2 divisors, whose sum is σ = 18916220880. Its totient is φ = 18916220878.

The previous prime is 18916220819. The next prime is 18916220951. The reversal of 18916220879 is 97802261981.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 18916220879 - 2⁸ = 18916220623 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18916220879.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18916220819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9458110439 + 9458110440.

It is an arithmetic number, because the mean of its divisors is an integer number (9458110440).

Almost surely, 2^18916220879 is an apocalyptic number.

18916220879 is a deficient number, since it is larger than the sum of its proper divisors (1).

18916220879 is an equidigital number, since it uses as much as digits as its factorization.

18916220879 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 870912, while the sum is 53.

The spelling of 18916220879 in words is "eighteen billion, nine hundred sixteen million, two hundred twenty thousand, eight hundred seventy-nine".