21897346 has 12 divisors (see below), whose sum is σ = 33942726. Its totient is φ = 10594560.

The previous prime is 21897313. The next prime is 21897371. The reversal of 21897346 is 64379812.

It can be written as a sum of positive squares in only one way, i.e., 16491721 + 5405625 = 4061^2 + 2325^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21897299 and 21897308.

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, 3775 + ... + 7618.

Almost surely, 2^21897346 is an apocalyptic number.

21897346 is a deficient number, since it is larger than the sum of its proper divisors (12045380).

21897346 is a wasteful number, since it uses less digits than its factorization.

21897346 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11457 (or 11426 counting only the distinct ones).

The product of its digits is 72576, while the sum is 40.

The square root of 21897346 is about 4679.4600115825. The cubic root of 21897346 is about 279.7674344376.

The spelling of 21897346 in words is "twenty-one million, eight hundred ninety-seven thousand, three hundred forty-six".