21719315 has 8 divisors (see below), whose sum is σ = 26089728. Its totient is φ = 17357760.

The previous prime is 21719309. The next prime is 21719339. The reversal of 21719315 is 51391712.

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

It is not a de Polignac number, because 21719315 - 2¹² = 21715219 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5879 + ... + 8831.

It is an arithmetic number, because the mean of its divisors is an integer number (3261216).

Almost surely, 2^21719315 is an apocalyptic number.

21719315 is a deficient number, since it is larger than the sum of its proper divisors (4370413).

21719315 is a wasteful number, since it uses less digits than its factorization.

21719315 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4429.

The product of its digits is 1890, while the sum is 29.

The square root of 21719315 is about 4660.3985881038. The cubic root of 21719315 is about 279.0071768386.

The spelling of 21719315 in words is "twenty-one million, seven hundred nineteen thousand, three hundred fifteen".