21677257946 has 4 divisors (see below), whose sum is σ = 32515886922. Its totient is φ = 10838628972.

The previous prime is 21677257919. The next prime is 21677257961. The reversal of 21677257946 is 64975277612.

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., 20613780625 + 1063477321 = 143575^2 + 32611^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21677257891 and 21677257900.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5419314485 + ... + 5419314488.

Almost surely, 2^21677257946 is an apocalyptic number.

21677257946 is a deficient number, since it is larger than the sum of its proper divisors (10838628976).

21677257946 is a wasteful number, since it uses less digits than its factorization.

21677257946 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10838628975.

The product of its digits is 8890560, while the sum is 56.

The spelling of 21677257946 in words is "twenty-one billion, six hundred seventy-seven million, two hundred fifty-seven thousand, nine hundred forty-six".