20121766 has 24 divisors (see below), whose sum is σ = 35745840. Its totient is φ = 8321376.

The previous prime is 20121763. The next prime is 20121767. The reversal of 20121766 is 66712102.

It is a self number, because there is not a number n which added to its sum of digits gives 20121766.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121763) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 10920 + ... + 12628.

It is an arithmetic number, because the mean of its divisors is an integer number (1489410).

Almost surely, 2^20121766 is an apocalyptic number.

20121766 is a deficient number, since it is larger than the sum of its proper divisors (15624074).

20121766 is a wasteful number, since it uses less digits than its factorization.

20121766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1776 (or 1747 counting only the distinct ones).

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 20121766 is about 4485.7291492019. The cubic root of 20121766 is about 271.9915204248.

Adding to 20121766 its reverse (66712102), we get a palindrome (86833868).

The spelling of 20121766 in words is "twenty million, one hundred twenty-one thousand, seven hundred sixty-six".