21293075 has 6 divisors (see below), whose sum is σ = 26403444. Its totient is φ = 17034440.

The previous prime is 21293057. The next prime is 21293081. The reversal of 21293075 is 57039212.

It is not a de Polignac number, because 21293075 - 2⁶ = 21293011 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 425837 + ... + 425886.

It is an arithmetic number, because the mean of its divisors is an integer number (4400574).

Almost surely, 2^21293075 is an apocalyptic number.

21293075 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21293075 is a deficient number, since it is larger than the sum of its proper divisors (5110369).

21293075 is an equidigital number, since it uses as much as digits as its factorization.

21293075 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 851733 (or 851728 counting only the distinct ones).

The product of its (nonzero) digits is 3780, while the sum is 29.

The square root of 21293075 is about 4614.4420031029. The cubic root of 21293075 is about 277.1699400753.

The spelling of 21293075 in words is "twenty-one million, two hundred ninety-three thousand, seventy-five".