21064719 has 8 divisors (see below), whose sum is σ = 30246832. Its totient is φ = 12962880.

The previous prime is 21064679. The next prime is 21064723. The reversal of 21064719 is 91746012.

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 21064719 - 2⁷ = 21064591 is a prime.

It is a super-2 number, since 2×21064719² = 887444773097922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21062719) 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, 270022 + ... + 270099.

It is an arithmetic number, because the mean of its divisors is an integer number (3780854).

Almost surely, 2^21064719 is an apocalyptic number.

21064719 is a deficient number, since it is larger than the sum of its proper divisors (9182113).

21064719 is a wasteful number, since it uses less digits than its factorization.

21064719 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 540137.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 21064719 is about 4589.6316845690. The cubic root of 21064719 is about 276.1755473212.

The spelling of 21064719 in words is "twenty-one million, sixty-four thousand, seven hundred nineteen".