20909994 has 32 divisors (see below), whose sum is σ = 50311680. Its totient is φ = 5659632.

The previous prime is 20909989. The next prime is 20910011. The reversal of 20909994 is 49990902.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12304 + ... + 13899.

It is an arithmetic number, because the mean of its divisors is an integer number (1572240).

Almost surely, 2^20909994 is an apocalyptic number.

20909994 is an abundant number, since it is smaller than the sum of its proper divisors (29401686).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20909994 is a wasteful number, since it uses less digits than its factorization.

20909994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26234.

The product of its (nonzero) digits is 52488, while the sum is 42.

The square root of 20909994 is about 4572.7446900084. The cubic root of 20909994 is about 275.4976948719.

The spelling of 20909994 in words is "twenty million, nine hundred nine thousand, nine hundred ninety-four".