21523210545 has 32 divisors (see below), whose sum is σ = 36258007680. Its totient is φ = 10872368640.

The previous prime is 21523210531. The next prime is 21523210567. The reversal of 21523210545 is 54501232512.

It is not a de Polignac number, because 21523210545 - 2⁴ = 21523210529 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2223015 + ... + 2232675.

It is an arithmetic number, because the mean of its divisors is an integer number (1133062740).

Almost surely, 2^21523210545 is an apocalyptic number.

It is an amenable number.

21523210545 is a deficient number, since it is larger than the sum of its proper divisors (14734797135).

21523210545 is a wasteful number, since it uses less digits than its factorization.

21523210545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17505.

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

The spelling of 21523210545 in words is "twenty-one billion, five hundred twenty-three million, two hundred ten thousand, five hundred forty-five".