21068525 has 24 divisors (see below), whose sum is σ = 28022760. Its totient is φ = 15656960.

The previous prime is 21068521. The next prime is 21068527. The reversal of 21068525 is 52586012.

It can be written as a sum of positive squares in 12 ways, for example, as 10738729 + 10329796 = 3277^2 + 3214^2 .

It is not a de Polignac number, because 21068525 - 2² = 21068521 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21068521) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 37547 + ... + 38103.

It is an arithmetic number, because the mean of its divisors is an integer number (1167615).

Almost surely, 2^21068525 is an apocalyptic number.

21068525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21068525 is a deficient number, since it is larger than the sum of its proper divisors (6954235).

21068525 is a wasteful number, since it uses less digits than its factorization.

21068525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 673 (or 668 counting only the distinct ones).

The product of its (nonzero) digits is 4800, while the sum is 29.

The square root of 21068525 is about 4590.0462960628. The cubic root of 21068525 is about 276.1921795683.

The spelling of 21068525 in words is "twenty-one million, sixty-eight thousand, five hundred twenty-five".