21881322 has 12 divisors (see below), whose sum is σ = 47409570. Its totient is φ = 7293768.

The previous prime is 21881297. The next prime is 21881351. The reversal of 21881322 is 22318812.

It can be written as a sum of positive squares in only one way, i.e., 11634921 + 10246401 = 3411^2 + 3201^2 .

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, 607797 + ... + 607832.

Almost surely, 2^21881322 is an apocalyptic number.

21881322 is an abundant number, since it is smaller than the sum of its proper divisors (25528248).

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

21881322 is a wasteful number, since it uses less digits than its factorization.

21881322 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1215637 (or 1215634 counting only the distinct ones).

The product of its digits is 1536, while the sum is 27.

The square root of 21881322 is about 4677.7475348719. The cubic root of 21881322 is about 279.6991752167.

The spelling of 21881322 in words is "twenty-one million, eight hundred eighty-one thousand, three hundred twenty-two".