20531886 has 32 divisors (see below), whose sum is σ = 43931808. Its totient is φ = 6374400.

The previous prime is 20531881. The next prime is 20531899. The reversal of 20531886 is 68813502.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20531881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9306 + ... + 11298.

It is an arithmetic number, because the mean of its divisors is an integer number (1372869).

Almost surely, 2^20531886 is an apocalyptic number.

20531886 is an abundant number, since it is smaller than the sum of its proper divisors (23399922).

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

20531886 is a wasteful number, since it uses less digits than its factorization.

20531886 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2116.

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 20531886 is about 4531.2124205338. The cubic root of 20531886 is about 273.8270082133.

The spelling of 20531886 in words is "twenty million, five hundred thirty-one thousand, eight hundred eighty-six".