21561052 has 12 divisors (see below), whose sum is σ = 37764496. Its totient is φ = 10771200.

The previous prime is 21561041. The next prime is 21561077. The reversal of 21561052 is 25016512.

It is a hoax number, since the sum of its digits (22) coincides with the sum of the digits of its distinct prime factors.

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, 7177 + ... + 9727.

Almost surely, 2^21561052 is an apocalyptic number.

It is an amenable number.

21561052 is a deficient number, since it is larger than the sum of its proper divisors (16203444).

21561052 is a wasteful number, since it uses less digits than its factorization.

21561052 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4668 (or 4666 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 22.

The square root of 21561052 is about 4643.3879872352. The cubic root of 21561052 is about 278.3278398603.

Adding to 21561052 its reverse (25016512), we get a palindrome (46577564).

The spelling of 21561052 in words is "twenty-one million, five hundred sixty-one thousand, fifty-two".