21356652 has 48 divisors (see below), whose sum is σ = 51270912. Its totient is φ = 6916800.

The previous prime is 21356633. The next prime is 21356653. The reversal of 21356652 is 25665312.

It is a super-2 number, since 2×21356652² = 912213169298208, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21356653) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 81073 + ... + 81335.

It is an arithmetic number, because the mean of its divisors is an integer number (1068144).

Almost surely, 2^21356652 is an apocalyptic number.

It is an amenable number.

21356652 is an abundant number, since it is smaller than the sum of its proper divisors (29914260).

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

21356652 is a wasteful number, since it uses less digits than its factorization.

21356652 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 438 (or 436 counting only the distinct ones).

The product of its digits is 10800, while the sum is 30.

The square root of 21356652 is about 4621.3257837984. The cubic root of 21356652 is about 277.4455245717.

It can be divided in two parts, 213 and 56652, that added together give a palindrome (56865).

The spelling of 21356652 in words is "twenty-one million, three hundred fifty-six thousand, six hundred fifty-two".