21383715 has 16 divisors (see below), whose sum is σ = 34272000. Its totient is φ = 11385312.

The previous prime is 21383711. The next prime is 21383723. The reversal of 21383715 is 51738312.

It is not a de Polignac number, because 21383715 - 2² = 21383711 is a prime.

It is a super-3 number, since 3×21383715³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (21383711) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14586 + ... + 15984.

It is an arithmetic number, because the mean of its divisors is an integer number (2142000).

Almost surely, 2^21383715 is an apocalyptic number.

21383715 is a deficient number, since it is larger than the sum of its proper divisors (12888285).

21383715 is a wasteful number, since it uses less digits than its factorization.

21383715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2426.

The product of its digits is 5040, while the sum is 30.

The square root of 21383715 is about 4624.2529126336. The cubic root of 21383715 is about 277.5626674473.

The spelling of 21383715 in words is "twenty-one million, three hundred eighty-three thousand, seven hundred fifteen".