21778711882 has 4 divisors (see below), whose sum is σ = 32668067826. Its totient is φ = 10889355940.

The previous prime is 21778711873. The next prime is 21778711897. The reversal of 21778711882 is 28811787712.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 19908927801 + 1869784081 = 141099^2 + 43241^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5444677969 + ... + 5444677972.

Almost surely, 2^21778711882 is an apocalyptic number.

21778711882 is a deficient number, since it is larger than the sum of its proper divisors (10889355944).

21778711882 is a wasteful number, since it uses less digits than its factorization.

21778711882 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10889355943.

The product of its digits is 702464, while the sum is 52.

The spelling of 21778711882 in words is "twenty-one billion, seven hundred seventy-eight million, seven hundred eleven thousand, eight hundred eighty-two".