21418719 has 16 divisors (see below), whose sum is σ = 34356480. Its totient is φ = 11594880.

The previous prime is 21418703. The next prime is 21418723. The reversal of 21418719 is 91781412.

It is not a de Polignac number, because 21418719 - 2⁴ = 21418703 is a prime.

It is a super-2 number, since 2×21418719² = 917523047201922, 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 21418719.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21413719) 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, 26442 + ... + 27239.

It is an arithmetic number, because the mean of its divisors is an integer number (2147280).

Almost surely, 2^21418719 is an apocalyptic number.

21418719 is a deficient number, since it is larger than the sum of its proper divisors (12937761).

21418719 is a wasteful number, since it uses less digits than its factorization.

21418719 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53710.

The product of its digits is 4032, while the sum is 33.

The square root of 21418719 is about 4628.0361925983. The cubic root of 21418719 is about 277.7140366397.

The spelling of 21418719 in words is "twenty-one million, four hundred eighteen thousand, seven hundred nineteen".