21669275 has 12 divisors (see below), whose sum is σ = 27174600. Its totient is φ = 17138880.

The previous prime is 21669269. The next prime is 21669281. The reversal of 21669275 is 57296612.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21669269) and next prime (21669281).

It is not a de Polignac number, because 21669275 - 2⁴ = 21669259 is a prime.

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, 2645 + ... + 7094.

It is an arithmetic number, because the mean of its divisors is an integer number (2264550).

Almost surely, 2^21669275 is an apocalyptic number.

21669275 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21669275 is a deficient number, since it is larger than the sum of its proper divisors (5505325).

21669275 is an equidigital number, since it uses as much as digits as its factorization.

21669275 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9838 (or 9833 counting only the distinct ones).

The product of its digits is 45360, while the sum is 38.

The square root of 21669275 is about 4655.0268527690. The cubic root of 21669275 is about 278.7927401335.

The spelling of 21669275 in words is "twenty-one million, six hundred sixty-nine thousand, two hundred seventy-five".