21556112387718 has 8 divisors (see below), whose sum is σ = 43112224775448. Its totient is φ = 7185370795904.

The previous prime is 21556112387699. The next prime is 21556112387749. The reversal of 21556112387718 is 81778321165512.

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

21556112387718 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1796342698971 + ... + 1796342698982.

It is an arithmetic number, because the mean of its divisors is an integer number (5389028096931).

Almost surely, 2^{21556112387718} is an apocalyptic number.

21556112387718 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.

21556112387718 is a wasteful number, since it uses less digits than its factorization.

21556112387718 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3592685397958.

The product of its digits is 5644800, while the sum is 57.

The spelling of 21556112387718 in words is "twenty-one trillion, five hundred fifty-six billion, one hundred twelve million, three hundred eighty-seven thousand, seven hundred eighteen".