21980508794 has 16 divisors (see below), whose sum is σ = 33380236032. Its totient is φ = 10854336528.

The previous prime is 21980508787. The next prime is 21980508833. The reversal of 21980508794 is 49780508912.

It is a super-2 number, since 2×21980508794² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 66194 + ... + 219869.

It is an arithmetic number, because the mean of its divisors is an integer number (2086264752).

Almost surely, 2^21980508794 is an apocalyptic number.

21980508794 is a deficient number, since it is larger than the sum of its proper divisors (11399727238).

21980508794 is a wasteful number, since it uses less digits than its factorization.

21980508794 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 286541.

The product of its (nonzero) digits is 1451520, while the sum is 53.

The spelling of 21980508794 in words is "twenty-one billion, nine hundred eighty million, five hundred eight thousand, seven hundred ninety-four".