20994171 has 16 divisors (see below), whose sum is σ = 30927360. Its totient is φ = 12561120.

The previous prime is 20994151. The next prime is 20994179. The reversal of 20994171 is 17149902.

It is not a de Polignac number, because 20994171 - 2⁵ = 20994139 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (20994179) 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 15 ways as a sum of consecutive naturals, for example, 1420 + ... + 6633.

It is an arithmetic number, because the mean of its divisors is an integer number (1932960).

Almost surely, 2^20994171 is an apocalyptic number.

20994171 is a deficient number, since it is larger than the sum of its proper divisors (9933189).

20994171 is a wasteful number, since it uses less digits than its factorization.

20994171 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8146.

The product of its (nonzero) digits is 4536, while the sum is 33.

The square root of 20994171 is about 4581.9396547750. The cubic root of 20994171 is about 275.8668886584.

It can be divided in two parts, 209941 and 71, that added together give a palindrome (210012).

The spelling of 20994171 in words is "twenty million, nine hundred ninety-four thousand, one hundred seventy-one".