21956275 has 12 divisors (see below), whose sum is σ = 29701224. Its totient is φ = 15968000.

The previous prime is 21956269. The next prime is 21956287. The reversal of 21956275 is 57265912.

It is not a de Polignac number, because 21956275 - 2⁵ = 21956243 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 39646 + ... + 40195.

It is an arithmetic number, because the mean of its divisors is an integer number (2475102).

Almost surely, 2^21956275 is an apocalyptic number.

21956275 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21956275 is a deficient number, since it is larger than the sum of its proper divisors (7744949).

21956275 is a wasteful number, since it uses less digits than its factorization.

21956275 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 79862 (or 79857 counting only the distinct ones).

The product of its digits is 37800, while the sum is 37.

The square root of 21956275 is about 4685.7523408733. The cubic root of 21956275 is about 280.0181748407.

The spelling of 21956275 in words is "twenty-one million, nine hundred fifty-six thousand, two hundred seventy-five".