18220402451 has 4 divisors (see below), whose sum is σ = 18220712400. Its totient is φ = 18220092504.

The previous prime is 18220402441. The next prime is 18220402481. The reversal of 18220402451 is 15420402281.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 15420402281 = 113 ⋅136463737.

It is a cyclic number.

It is not a de Polignac number, because 18220402451 - 2²² = 18216208147 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18220402411) 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, 36716 + ... + 194393.

It is an arithmetic number, because the mean of its divisors is an integer number (4555178100).

Almost surely, 2^18220402451 is an apocalyptic number.

18220402451 is a deficient number, since it is larger than the sum of its proper divisors (309949).

18220402451 is an equidigital number, since it uses as much as digits as its factorization.

18220402451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 309948.

The product of its (nonzero) digits is 5120, while the sum is 29.

The spelling of 18220402451 in words is "eighteen billion, two hundred twenty million, four hundred two thousand, four hundred fifty-one".