21552641 has 12 divisors (see below), whose sum is σ = 24099600. Its totient is φ = 19254840.

The previous prime is 21552637. The next prime is 21552653. The reversal of 21552641 is 14625512.

It is not a de Polignac number, because 21552641 - 2² = 21552637 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21552641.

It is not an unprimeable number, because it can be changed into a prime (21552691) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5630 + ... + 8648.

It is an arithmetic number, because the mean of its divisors is an integer number (2008300).

Almost surely, 2^21552641 is an apocalyptic number.

It is an amenable number.

21552641 is a deficient number, since it is larger than the sum of its proper divisors (2546959).

21552641 is a wasteful number, since it uses less digits than its factorization.

21552641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3100 (or 3089 counting only the distinct ones).

The product of its digits is 2400, while the sum is 26.

The square root of 21552641 is about 4642.4822024430. The cubic root of 21552641 is about 278.2916431117.

The spelling of 21552641 in words is "twenty-one million, five hundred fifty-two thousand, six hundred forty-one".