21719379 has 12 divisors (see below), whose sum is σ = 31831688. Its totient is φ = 13163040.

The previous prime is 21719359. The next prime is 21719389. The reversal of 21719379 is 97391712.

It is not a de Polignac number, because 21719379 - 2¹⁹ = 21195091 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21719309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 29554 + ... + 30279.

Almost surely, 2^21719379 is an apocalyptic number.

21719379 is a deficient number, since it is larger than the sum of its proper divisors (10112309).

21719379 is a wasteful number, since it uses less digits than its factorization.

21719379 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59858 (or 59847 counting only the distinct ones).

The product of its digits is 23814, while the sum is 39.

The square root of 21719379 is about 4660.4054544642. The cubic root of 21719379 is about 279.0074508872.

It can be divided in two parts, 21 and 719379, that added together give a triangular number (719400 = T₁₁₉₉).

The spelling of 21719379 in words is "twenty-one million, seven hundred nineteen thousand, three hundred seventy-nine".