21778986274 has 8 divisors (see below), whose sum is σ = 32669110188. Its totient is φ = 10889282880.

The previous prime is 21778986269. The next prime is 21778986293. The reversal of 21778986274 is 47268987712.

It can be written as a sum of positive squares in 2 ways, for example, as 17834267025 + 3944719249 = 133545^2 + 62807^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 125814 + ... + 243694.

Almost surely, 2^21778986274 is an apocalyptic number.

21778986274 is a deficient number, since it is larger than the sum of its proper divisors (10890123914).

21778986274 is a wasteful number, since it uses less digits than its factorization.

21778986274 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 210260.

The product of its digits is 18966528, while the sum is 61.

The spelling of 21778986274 in words is "twenty-one billion, seven hundred seventy-eight million, nine hundred eighty-six thousand, two hundred seventy-four".