21875719 has 4 divisors (see below), whose sum is σ = 23162544. Its totient is φ = 20588896.

The previous prime is 21875713. The next prime is 21875747. The reversal of 21875719 is 91757812.

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 21875719 - 2⁹ = 21875207 is a prime.

It is a super-2 number, since 2×21875719² = 957094163533922, which contains 22 as substring.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21875713) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 643387 + ... + 643420.

It is an arithmetic number, because the mean of its divisors is an integer number (5790636).

Almost surely, 2^21875719 is an apocalyptic number.

21875719 is a deficient number, since it is larger than the sum of its proper divisors (1286825).

21875719 is a wasteful number, since it uses less digits than its factorization.

21875719 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1286824.

The product of its digits is 35280, while the sum is 40.

The square root of 21875719 is about 4677.1485971690. The cubic root of 21875719 is about 279.6752996291.

The spelling of 21875719 in words is "twenty-one million, eight hundred seventy-five thousand, seven hundred nineteen".