21562545 has 16 divisors (see below), whose sum is σ = 36529920. Its totient is φ = 10823424.

The previous prime is 21562507. The next prime is 21562559. The reversal of 21562545 is 54526512.

It is not a de Polignac number, because 21562545 - 2⁷ = 21562417 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42025 + ... + 42534.

It is an arithmetic number, because the mean of its divisors is an integer number (2283120).

Almost surely, 2^21562545 is an apocalyptic number.

It is an amenable number.

21562545 is a deficient number, since it is larger than the sum of its proper divisors (14967375).

21562545 is a wasteful number, since it uses less digits than its factorization.

21562545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84584.

The product of its digits is 12000, while the sum is 30.

The square root of 21562545 is about 4643.5487506863. The cubic root of 21562545 is about 278.3342640038.

The spelling of 21562545 in words is "twenty-one million, five hundred sixty-two thousand, five hundred forty-five".