21373719 has 8 divisors (see below), whose sum is σ = 28723200. Its totient is φ = 14136696.

The previous prime is 21373717. The next prime is 21373771. The reversal of 21373719 is 91737312.

It is a happy number.

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

It is not a de Polignac number, because 21373719 - 2¹ = 21373717 is a prime.

It is a super-2 number, since 2×21373719² = 913671727781922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21373719.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21373711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27669 + ... + 28430.

It is an arithmetic number, because the mean of its divisors is an integer number (3590400).

Almost surely, 2^21373719 is an apocalyptic number.

21373719 is a deficient number, since it is larger than the sum of its proper divisors (7349481).

21373719 is a wasteful number, since it uses less digits than its factorization.

21373719 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 56229.

The product of its digits is 7938, while the sum is 33.

The square root of 21373719 is about 4623.1719630574. The cubic root of 21373719 is about 277.5194110275.

The spelling of 21373719 in words is "twenty-one million, three hundred seventy-three thousand, seven hundred nineteen".