21302072 has 16 divisors (see below), whose sum is σ = 43572600. Its totient is φ = 9682720.

The previous prime is 21302063. The next prime is 21302081. The reversal of 21302072 is 27020312.

It is an interprime number because it is at equal distance from previous prime (21302063) and next prime (21302081).

It is a self number, because there is not a number n which added to its sum of digits gives 21302072.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 120947 + ... + 121122.

Almost surely, 2^21302072 is an apocalyptic number.

21302072 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

21302072 is an abundant number, since it is smaller than the sum of its proper divisors (22270528).

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

21302072 is a wasteful number, since it uses less digits than its factorization.

21302072 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 242086 (or 242082 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 17.

The square root of 21302072 is about 4615.4167742469. The cubic root of 21302072 is about 277.2089722773.

Adding to 21302072 its reverse (27020312), we get a palindrome (48322384).

The spelling of 21302072 in words is "twenty-one million, three hundred two thousand, seventy-two".