21712475 has 12 divisors (see below), whose sum is σ = 27193200. Its totient is φ = 17196000.

The previous prime is 21712469. The next prime is 21712477. The reversal of 21712475 is 57421712.

It is not a de Polignac number, because 21712475 - 2¹⁰ = 21711451 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21712477) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1775 + ... + 6824.

It is an arithmetic number, because the mean of its divisors is an integer number (2266100).

Almost surely, 2^21712475 is an apocalyptic number.

21712475 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21712475 is a deficient number, since it is larger than the sum of its proper divisors (5480725).

21712475 is a wasteful number, since it uses less digits than its factorization.

21712475 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8710 (or 8705 counting only the distinct ones).

The product of its digits is 3920, while the sum is 29.

The square root of 21712475 is about 4659.6646875070. The cubic root of 21712475 is about 278.9778847936.

The spelling of 21712475 in words is "twenty-one million, seven hundred twelve thousand, four hundred seventy-five".