20808831 has 8 divisors (see below), whose sum is σ = 27833904. Its totient is φ = 13828160.

The previous prime is 20808829. The next prime is 20808841. The reversal of 20808831 is 13880802.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20808831 - 2¹ = 20808829 is a prime.

It is a super-2 number, since 2×20808831² = 866014895173122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20808841) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9990 + ... + 11891.

It is an arithmetic number, because the mean of its divisors is an integer number (3479238).

Almost surely, 2^20808831 is an apocalyptic number.

20808831 is a deficient number, since it is larger than the sum of its proper divisors (7025073).

20808831 is a wasteful number, since it uses less digits than its factorization.

20808831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22201.

The product of its (nonzero) digits is 3072, while the sum is 30.

The square root of 20808831 is about 4561.6697600769. The cubic root of 20808831 is about 275.0526885271.

The spelling of 20808831 in words is "twenty million, eight hundred eight thousand, eight hundred thirty-one".