20881869 has 16 divisors (see below), whose sum is σ = 28543872. Its totient is φ = 13575168.

The previous prime is 20881867. The next prime is 20881873. The reversal of 20881869 is 96818802.

It is not a de Polignac number, because 20881869 - 2¹ = 20881867 is a prime.

It is a super-2 number, since 2×20881869² = 872104905866322, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20881869.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20881867) 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, 20752 + ... + 21734.

It is an arithmetic number, because the mean of its divisors is an integer number (1783992).

Almost surely, 2^20881869 is an apocalyptic number.

It is an amenable number.

20881869 is a deficient number, since it is larger than the sum of its proper divisors (7662003).

20881869 is an equidigital number, since it uses as much as digits as its factorization.

20881869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1156.

The product of its (nonzero) digits is 55296, while the sum is 42.

The square root of 20881869 is about 4569.6683687112. The cubic root of 20881869 is about 275.3741200038.

The spelling of 20881869 in words is "twenty million, eight hundred eighty-one thousand, eight hundred sixty-nine".