21020332 has 6 divisors (see below), whose sum is σ = 36785588. Its totient is φ = 10510164.

The previous prime is 21020303. The next prime is 21020339. The reversal of 21020332 is 23302012.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21020339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2627538 + ... + 2627545.

Almost surely, 2^21020332 is an apocalyptic number.

It is an amenable number.

21020332 is a deficient number, since it is larger than the sum of its proper divisors (15765256).

21020332 is a wasteful number, since it uses less digits than its factorization.

21020332 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5255087 (or 5255085 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 13.

The square root of 21020332 is about 4584.7935613286. The cubic root of 21020332 is about 275.9814277218.

Adding to 21020332 its reverse (23302012), we get a palindrome (44322344).

The spelling of 21020332 in words is "twenty-one million, twenty thousand, three hundred thirty-two".