21618623874 has 8 divisors (see below), whose sum is σ = 43237247760. Its totient is φ = 7206207956.

The previous prime is 21618623849. The next prime is 21618623879. The reversal of 21618623874 is 47832681612.

It is a sphenic number, since it is the product of 3 distinct primes.

21618623874 is an admirable number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (21618623879) 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, 1801551984 + ... + 1801551995.

It is an arithmetic number, because the mean of its divisors is an integer number (5404655970).

Almost surely, 2^21618623874 is an apocalyptic number.

21618623874 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21618623874 is a wasteful number, since it uses less digits than its factorization.

21618623874 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3603103984.

The product of its digits is 774144, while the sum is 48.

The spelling of 21618623874 in words is "twenty-one billion, six hundred eighteen million, six hundred twenty-three thousand, eight hundred seventy-four".