21550653 has 12 divisors (see below), whose sum is σ = 31203900. Its totient is φ = 14332416.

The previous prime is 21550643. The next prime is 21550657. The reversal of 21550653 is 35605512.

21550653 is a `hidden beast` number, since 2 + 1 + 5 + 5 + 0 + 653 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 18818244 + 2732409 = 4338^2 + 1653^2 .

It is not a de Polignac number, because 21550653 - 2⁴ = 21550637 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21550657) 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 11 ways as a sum of consecutive naturals, for example, 1375 + ... + 6707.

It is an arithmetic number, because the mean of its divisors is an integer number (2600325).

Almost surely, 2^21550653 is an apocalyptic number.

It is an amenable number.

21550653 is a deficient number, since it is larger than the sum of its proper divisors (9653247).

21550653 is a wasteful number, since it uses less digits than its factorization.

21550653 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5788 (or 5785 counting only the distinct ones).

The product of its (nonzero) digits is 4500, while the sum is 27.

The square root of 21550653 is about 4642.2680879070. The cubic root of 21550653 is about 278.2830863754.

The spelling of 21550653 in words is "twenty-one million, five hundred fifty thousand, six hundred fifty-three".