20683881 has 6 divisors (see below), whose sum is σ = 29876730. Its totient is φ = 13789248.

The previous prime is 20683879. The next prime is 20683889. The reversal of 20683881 is 18838602.

It can be written as a sum of positive squares in only one way, i.e., 10949481 + 9734400 = 3309^2 + 3120^2 .

It is not a de Polignac number, because 20683881 - 2¹ = 20683879 is a prime.

It is a super-2 number, since 2×20683881² = 855645866444322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20683889) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1149096 + ... + 1149113.

It is an arithmetic number, because the mean of its divisors is an integer number (4979455).

Almost surely, 2^20683881 is an apocalyptic number.

It is an amenable number.

20683881 is a deficient number, since it is larger than the sum of its proper divisors (9192849).

20683881 is a wasteful number, since it uses less digits than its factorization.

20683881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2298215 (or 2298212 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 36.

The square root of 20683881 is about 4547.9534958045. The cubic root of 20683881 is about 274.5010500920.

The spelling of 20683881 in words is "twenty million, six hundred eighty-three thousand, eight hundred eighty-one".