21403675 has 6 divisors (see below), whose sum is σ = 26540588. Its totient is φ = 17122920.

The previous prime is 21403667. The next prime is 21403687. The reversal of 21403675 is 57630412.

It is not a de Polignac number, because 21403675 - 2³ = 21403667 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 (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 428049 + ... + 428098.

Almost surely, 2^21403675 is an apocalyptic number.

21403675 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21403675 is a deficient number, since it is larger than the sum of its proper divisors (5136913).

21403675 is an equidigital number, since it uses as much as digits as its factorization.

21403675 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 856157 (or 856152 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 28.

The square root of 21403675 is about 4626.4105956994. The cubic root of 21403675 is about 277.6490014944.

The spelling of 21403675 in words is "twenty-one million, four hundred three thousand, six hundred seventy-five".