21752719 has 2 divisors, whose sum is σ = 21752720. Its totient is φ = 21752718.

The previous prime is 21752699. The next prime is 21752747. The reversal of 21752719 is 91725712.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21752719 - 2¹¹ = 21750671 is a prime.

It is a super-2 number, since 2×21752719² = 946361567785922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21752219) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10876359 + 10876360.

It is an arithmetic number, because the mean of its divisors is an integer number (10876360).

Almost surely, 2^21752719 is an apocalyptic number.

21752719 is a deficient number, since it is larger than the sum of its proper divisors (1).

21752719 is an equidigital number, since it uses as much as digits as its factorization.

21752719 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8820, while the sum is 34.

The square root of 21752719 is about 4663.9810248328. The cubic root of 21752719 is about 279.1501399389.

The spelling of 21752719 in words is "twenty-one million, seven hundred fifty-two thousand, seven hundred nineteen".