21755652 has 48 divisors (see below), whose sum is σ = 52496640. Its totient is φ = 7008768.

The previous prime is 21755651. The next prime is 21755653. The reversal of 21755652 is 25655712.

It is an interprime number because it is at equal distance from previous prime (21755651) and next prime (21755653).

It is not an unprimeable number, because it can be changed into a prime (21755651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 50028 + ... + 50460.

It is an arithmetic number, because the mean of its divisors is an integer number (1093680).

Almost surely, 2^21755652 is an apocalyptic number.

It is an amenable number.

21755652 is an abundant number, since it is smaller than the sum of its proper divisors (30740988).

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

21755652 is a wasteful number, since it uses less digits than its factorization.

21755652 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 572 (or 570 counting only the distinct ones).

The product of its digits is 21000, while the sum is 33.

The square root of 21755652 is about 4664.2954451878. The cubic root of 21755652 is about 279.1626856589.

The spelling of 21755652 in words is "twenty-one million, seven hundred fifty-five thousand, six hundred fifty-two".