21292275 has 24 divisors (see below), whose sum is σ = 35694640. Its totient is φ = 11197440.

The previous prime is 21292253. The next prime is 21292277. The reversal of 21292275 is 57229212.

It is not a de Polignac number, because 21292275 - 2⁷ = 21292147 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21292277) by changing a digit.

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 23 ways as a sum of consecutive naturals, for example, 3531 + ... + 7419.

Almost surely, 2^21292275 is an apocalyptic number.

21292275 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21292275 is a deficient number, since it is larger than the sum of its proper divisors (14402365).

21292275 is a wasteful number, since it uses less digits than its factorization.

21292275 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3975 (or 3970 counting only the distinct ones).

The product of its digits is 5040, while the sum is 30.

The square root of 21292275 is about 4614.3553179182. The cubic root of 21292275 is about 277.1664688571.

The spelling of 21292275 in words is "twenty-one million, two hundred ninety-two thousand, two hundred seventy-five".