21560845 has 24 divisors (see below), whose sum is σ = 28204704. Its totient is φ = 15810816.

The previous prime is 21560843. The next prime is 21560863. The reversal of 21560845 is 54806512.

It is not a de Polignac number, because 21560845 - 2¹ = 21560843 is a prime.

It is a super-2 number, since 2×21560845² = 929740074228050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21560843) 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 23 ways as a sum of consecutive naturals, for example, 61962 + ... + 62308.

It is an arithmetic number, because the mean of its divisors is an integer number (1175196).

Almost surely, 2^21560845 is an apocalyptic number.

It is an amenable number.

21560845 is a deficient number, since it is larger than the sum of its proper divisors (6643859).

21560845 is a wasteful number, since it uses less digits than its factorization.

21560845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 429 (or 412 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 31.

The square root of 21560845 is about 4643.3656974225. The cubic root of 21560845 is about 278.3269491486.

The spelling of 21560845 in words is "twenty-one million, five hundred sixty thousand, eight hundred forty-five".