21373722 has 12 divisors (see below), whose sum is σ = 46309770. Its totient is φ = 7124568.

The previous prime is 21373717. The next prime is 21373771. The reversal of 21373722 is 22737312.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 14356521 + 7017201 = 3789^2 + 2649^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 593697 + ... + 593732.

Almost surely, 2^21373722 is an apocalyptic number.

21373722 is an abundant number, since it is smaller than the sum of its proper divisors (24936048).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21373722 is a wasteful number, since it uses less digits than its factorization.

21373722 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1187437 (or 1187434 counting only the distinct ones).

The product of its digits is 3528, while the sum is 27.

The square root of 21373722 is about 4623.1722875100. The cubic root of 21373722 is about 277.5194240117.

The spelling of 21373722 in words is "twenty-one million, three hundred seventy-three thousand, seven hundred twenty-two".