21053625 has 32 divisors (see below), whose sum is σ = 36571392. Its totient is φ = 10736000.

The previous prime is 21053609. The next prime is 21053639. The reversal of 21053625 is 52635012.

It is not a de Polignac number, because 21053625 - 2⁴ = 21053609 is a prime.

It is a hoax number, since the sum of its digits (24) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 21053595 and 21053604.

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, 7405 + ... + 9845.

It is an arithmetic number, because the mean of its divisors is an integer number (1142856).

Almost surely, 2^21053625 is an apocalyptic number.

21053625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21053625 is a deficient number, since it is larger than the sum of its proper divisors (15517767).

21053625 is a wasteful number, since it uses less digits than its factorization.

21053625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2482 (or 2472 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 24.

The square root of 21053625 is about 4588.4229316836. The cubic root of 21053625 is about 276.1270550285.

Adding to 21053625 its reverse (52635012), we get a palindrome (73688637).

It can be divided in two parts, 210 and 53625, that added together give a palindrome (53835).

The spelling of 21053625 in words is "twenty-one million, fifty-three thousand, six hundred twenty-five".