21954825 has 18 divisors (see below), whose sum is σ = 39323934. Its totient is φ = 11709120.

The previous prime is 21954809. The next prime is 21954841. The reversal of 21954825 is 52845912.

It is an interprime number because it is at equal distance from previous prime (21954809) and next prime (21954841).

It can be written as a sum of positive squares in 3 ways, for example, as 24336 + 21930489 = 156^2 + 4683^2 .

It is not a de Polignac number, because 21954825 - 2⁴ = 21954809 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21954825.

It is an unprimeable number.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 48564 + ... + 49013.

It is an arithmetic number, because the mean of its divisors is an integer number (2184663).

Almost surely, 2^21954825 is an apocalyptic number.

21954825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21954825 is a deficient number, since it is larger than the sum of its proper divisors (17369109).

21954825 is a wasteful number, since it uses less digits than its factorization.

21954825 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97593 (or 97585 counting only the distinct ones).

The product of its digits is 28800, while the sum is 36.

The square root of 21954825 is about 4685.5976139656. The cubic root of 21954825 is about 280.0120105392.

The spelling of 21954825 in words is "twenty-one million, nine hundred fifty-four thousand, eight hundred twenty-five".