20911104 has 66 divisors (see below), whose sum is σ = 60406970. Its totient is φ = 6967296.

The previous prime is 20911087. The next prime is 20911123. The reversal of 20911104 is 40111902.

It can be written as a sum of positive squares in only one way, i.e., 12616704 + 8294400 = 3552^2 + 2880^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 8082 + ... + 10350.

Almost surely, 2^20911104 is an apocalyptic number.

20911104 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20911104, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30203485).

20911104 is an abundant number, since it is smaller than the sum of its proper divisors (39495866).

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

20911104 is a wasteful number, since it uses less digits than its factorization.

20911104 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2295 (or 2274 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 18.

The square root of 20911104 is about 4572.8660597048. The cubic root of 20911104 is about 275.5025696865.

The spelling of 20911104 in words is "twenty million, nine hundred eleven thousand, one hundred four".