21590332 has 12 divisors (see below), whose sum is σ = 38208240. Its totient is φ = 10673696.

The previous prime is 21590329. The next prime is 21590339. The reversal of 21590332 is 23309512.

It is a happy number.

It is a super-2 number, since 2×21590332² = 932284871740448, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21590297 and 21590306.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21590339) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29968 + ... + 30679.

It is an arithmetic number, because the mean of its divisors is an integer number (3184020).

Almost surely, 2^21590332 is an apocalyptic number.

It is an amenable number.

21590332 is a deficient number, since it is larger than the sum of its proper divisors (16617908).

21590332 is a wasteful number, since it uses less digits than its factorization.

21590332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60740 (or 60738 counting only the distinct ones).

The product of its (nonzero) digits is 1620, while the sum is 25.

The square root of 21590332 is about 4646.5397878421. The cubic root of 21590332 is about 278.4537730003.

Adding to 21590332 its reverse (23309512), we get a palindrome (44899844).

The spelling of 21590332 in words is "twenty-one million, five hundred ninety thousand, three hundred thirty-two".