20111880 has 64 divisors (see below), whose sum is σ = 63518400. Its totient is φ = 5080320.

The previous prime is 20111879. The next prime is 20111881. The reversal of 20111880 is 8811102.

It is an interprime number because it is at equal distance from previous prime (20111879) and next prime (20111881).

It is not an unprimeable number, because it can be changed into a prime (20111881) 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, 2131 + ... + 6690.

It is an arithmetic number, because the mean of its divisors is an integer number (992475).

Almost surely, 2^20111880 is an apocalyptic number.

20111880 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20111880 is an abundant number, since it is smaller than the sum of its proper divisors (43406520).

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

20111880 is a wasteful number, since it uses less digits than its factorization.

20111880 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8854 (or 8850 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 21.

The square root of 20111880 is about 4484.6270747967. The cubic root of 20111880 is about 271.9469691886.

Adding to 20111880 its reverse (8811102), we get a palindrome (28922982).

The spelling of 20111880 in words is "twenty million, one hundred eleven thousand, eight hundred eighty".