18718006820 has 24 divisors (see below), whose sum is σ = 40049473464. Its totient is φ = 7345934336.

The previous prime is 18718006817. The next prime is 18718006823. The reversal of 18718006820 is 2860081781.

It is an interprime number because it is at equal distance from previous prime (18718006817) and next prime (18718006823).

It can be written as a sum of positive squares in 4 ways, for example, as 9441620224 + 9276386596 = 97168^2 + 96314^2 .

It is not an unprimeable number, because it can be changed into a prime (18718006823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8828189 + ... + 8830308.

It is an arithmetic number, because the mean of its divisors is an integer number (1668728061).

Almost surely, 2^18718006820 is an apocalyptic number.

18718006820 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

18718006820 is an abundant number, since it is smaller than the sum of its proper divisors (21331466644).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18718006820 is a wasteful number, since it uses less digits than its factorization.

18718006820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17658559 (or 17658557 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 41.

The spelling of 18718006820 in words is "eighteen billion, seven hundred eighteen million, six thousand, eight hundred twenty".