21436625 has 16 divisors (see below), whose sum is σ = 30576000. Its totient is φ = 14698800.

The previous prime is 21436601. The next prime is 21436637. The reversal of 21436625 is 52663412.

It is not a de Polignac number, because 21436625 - 2⁶ = 21436561 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11375 + ... + 13124.

It is an arithmetic number, because the mean of its divisors is an integer number (1911000).

Almost surely, 2^21436625 is an apocalyptic number.

21436625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21436625 is a deficient number, since it is larger than the sum of its proper divisors (9139375).

21436625 is an equidigital number, since it uses as much as digits as its factorization.

21436625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24521 (or 24511 counting only the distinct ones).

The product of its digits is 8640, while the sum is 29.

The square root of 21436625 is about 4629.9703022806. The cubic root of 21436625 is about 277.7914045167.

The spelling of 21436625 in words is "twenty-one million, four hundred thirty-six thousand, six hundred twenty-five".