21458275 has 12 divisors (see below), whose sum is σ = 27046384. Its totient is φ = 16884000.

The previous prime is 21458257. The next prime is 21458279. The reversal of 21458275 is 57285412.

It is a happy number.

It is not a de Polignac number, because 21458275 - 2¹³ = 21450083 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21458275.

It is not an unprimeable number, because it can be changed into a prime (21458279) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5511 + ... + 8560.

Almost surely, 2^21458275 is an apocalyptic number.

21458275 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

21458275 is a deficient number, since it is larger than the sum of its proper divisors (5588109).

21458275 is a wasteful number, since it uses less digits than its factorization.

21458275 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14142 (or 14137 counting only the distinct ones).

The product of its digits is 22400, while the sum is 34.

The square root of 21458275 is about 4632.3077402090. The cubic root of 21458275 is about 277.8848918755.

The spelling of 21458275 in words is "twenty-one million, four hundred fifty-eight thousand, two hundred seventy-five".