21225975 has 24 divisors (see below), whose sum is σ = 36046800. Its totient is φ = 11013120.

The previous prime is 21225973. The next prime is 21225989. The reversal of 21225975 is 57952212.

It is a happy number.

It is not a de Polignac number, because 21225975 - 2¹ = 21225973 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21225973) 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, 1050 + ... + 6599.

It is an arithmetic number, because the mean of its divisors is an integer number (1501950).

Almost surely, 2^21225975 is an apocalyptic number.

21225975 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21225975 is a deficient number, since it is larger than the sum of its proper divisors (14820825).

21225975 is a wasteful number, since it uses less digits than its factorization.

21225975 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7699 (or 7694 counting only the distinct ones).

The product of its digits is 12600, while the sum is 33.

The square root of 21225975 is about 4607.1656145617. The cubic root of 21225975 is about 276.8784889335.

The spelling of 21225975 in words is "twenty-one million, two hundred twenty-five thousand, nine hundred seventy-five".