21092919 has 16 divisors (see below), whose sum is σ = 29052672. Its totient is φ = 13603968.

The previous prime is 21092881. The next prime is 21092933. The reversal of 21092919 is 91929012.

It is not a de Polignac number, because 21092919 - 2⁸ = 21092663 is a prime.

It is a super-2 number, since 2×21092919² = 889822463881122, 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 21092919.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21092969) 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 15 ways as a sum of consecutive naturals, for example, 13854 + ... + 15300.

It is an arithmetic number, because the mean of its divisors is an integer number (1815792).

Almost surely, 2^21092919 is an apocalyptic number.

21092919 is a deficient number, since it is larger than the sum of its proper divisors (7959753).

21092919 is a wasteful number, since it uses less digits than its factorization.

21092919 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1606.

The product of its (nonzero) digits is 2916, while the sum is 33.

The square root of 21092919 is about 4592.7027990063. The cubic root of 21092919 is about 276.2987339887.

The spelling of 21092919 in words is "twenty-one million, ninety-two thousand, nine hundred nineteen".