18220465787 has 4 divisors (see below), whose sum is σ = 18222412920. Its totient is φ = 18218518656.

The previous prime is 18220465771. The next prime is 18220465799. The reversal of 18220465787 is 78756402281.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18220465787 - 2⁴ = 18220465771 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18220465387) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 959462 + ... + 978267.

It is an arithmetic number, because the mean of its divisors is an integer number (4555603230).

Almost surely, 2^18220465787 is an apocalyptic number.

18220465787 is a deficient number, since it is larger than the sum of its proper divisors (1947133).

18220465787 is an equidigital number, since it uses as much as digits as its factorization.

18220465787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1947132.

The product of its (nonzero) digits is 1505280, while the sum is 50.

The spelling of 18220465787 in words is "eighteen billion, two hundred twenty million, four hundred sixty-five thousand, seven hundred eighty-seven".