21275479 has 8 divisors (see below), whose sum is σ = 21546000. Its totient is φ = 21006912.

The previous prime is 21275477. The next prime is 21275489. The reversal of 21275479 is 97457212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21275479 - 2¹ = 21275477 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21275477) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 37107 + ... + 37675.

It is an arithmetic number, because the mean of its divisors is an integer number (2693250).

Almost surely, 2^21275479 is an apocalyptic number.

21275479 is a deficient number, since it is larger than the sum of its proper divisors (270521).

21275479 is a wasteful number, since it uses less digits than its factorization.

21275479 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 977.

The product of its digits is 35280, while the sum is 37.

The square root of 21275479 is about 4612.5349863172. The cubic root of 21275479 is about 277.0935705466.

The spelling of 21275479 in words is "twenty-one million, two hundred seventy-five thousand, four hundred seventy-nine".