21685422754 has 4 divisors (see below), whose sum is σ = 32528134134. Its totient is φ = 10842711376.

The previous prime is 21685422641. The next prime is 21685422767. The reversal of 21685422754 is 45722458612.

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., 11729973025 + 9955449729 = 108305^2 + 99777^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5421355687 + ... + 5421355690.

Almost surely, 2^21685422754 is an apocalyptic number.

21685422754 is a deficient number, since it is larger than the sum of its proper divisors (10842711380).

21685422754 is a wasteful number, since it uses less digits than its factorization.

21685422754 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10842711379.

The product of its digits is 1075200, while the sum is 46.

The spelling of 21685422754 in words is "twenty-one billion, six hundred eighty-five million, four hundred twenty-two thousand, seven hundred fifty-four".