21422615 has 4 divisors (see below), whose sum is σ = 25707144. Its totient is φ = 17138088.

The previous prime is 21422587. The next prime is 21422627. The reversal of 21422615 is 51622412.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21422615 - 2⁶ = 21422551 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2142257 + ... + 2142266.

It is an arithmetic number, because the mean of its divisors is an integer number (6426786).

Almost surely, 2^21422615 is an apocalyptic number.

21422615 is a deficient number, since it is larger than the sum of its proper divisors (4284529).

21422615 is an equidigital number, since it uses as much as digits as its factorization.

21422615 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4284528.

The product of its digits is 960, while the sum is 23.

The square root of 21422615 is about 4628.4570863302. The cubic root of 21422615 is about 277.7308740658.

The spelling of 21422615 in words is "twenty-one million, four hundred twenty-two thousand, six hundred fifteen".