21037825 has 12 divisors (see below), whose sum is σ = 26248320. Its totient is φ = 16726160.

The previous prime is 21037817. The next prime is 21037829. The reversal of 21037825 is 52873012.

It is not a de Polignac number, because 21037825 - 2³ = 21037817 is a prime.

It is a super-3 number, since 3×21037825³ (a number of 23 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21037793 and 21037802.

It is not an unprimeable number, because it can be changed into a prime (21037829) 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, 1656 + ... + 6694.

It is an arithmetic number, because the mean of its divisors is an integer number (2187360).

Almost surely, 2^21037825 is an apocalyptic number.

21037825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21037825 is a deficient number, since it is larger than the sum of its proper divisors (5210495).

21037825 is a wasteful number, since it uses less digits than its factorization.

21037825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5216 (or 5211 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 21037825 is about 4586.7008840778. The cubic root of 21037825 is about 276.0579632165.

The spelling of 21037825 in words is "twenty-one million, thirty-seven thousand, eight hundred twenty-five".