20858919 has 16 divisors (see below), whose sum is σ = 28477440. Its totient is φ = 13576640.

The previous prime is 20858899. The next prime is 20858927. The reversal of 20858919 is 91985802.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 20858919 - 2⁹ = 20858407 is a prime.

It is a super-2 number, since 2×20858919² = 870189003697122, which contains 22 as substring.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20858969) 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, 33499 + ... + 34115.

It is an arithmetic number, because the mean of its divisors is an integer number (1779840).

Almost surely, 2^20858919 is an apocalyptic number.

20858919 is a deficient number, since it is larger than the sum of its proper divisors (7618521).

20858919 is a wasteful number, since it uses less digits than its factorization.

20858919 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 870.

The product of its (nonzero) digits is 51840, while the sum is 42.

The square root of 20858919 is about 4567.1565552322. The cubic root of 20858919 is about 275.2732006733.

The spelling of 20858919 in words is "twenty million, eight hundred fifty-eight thousand, nine hundred nineteen".