20731120 has 40 divisors (see below), whose sum is σ = 48389760. Its totient is φ = 8259840.

The previous prime is 20731097. The next prime is 20731121. The reversal of 20731120 is 2113702.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a junction number, because it is equal to n+sod(n) for n = 20731094 and 20731103.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20731121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38050 + ... + 38590.

It is an arithmetic number, because the mean of its divisors is an integer number (1209744).

Almost surely, 2^20731120 is an apocalyptic number.

20731120 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20731120 is an abundant number, since it is smaller than the sum of its proper divisors (27658640).

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

20731120 is a wasteful number, since it uses less digits than its factorization.

20731120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1033 (or 1027 counting only the distinct ones).

The product of its (nonzero) digits is 84, while the sum is 16.

The square root of 20731120 is about 4553.1439687319. The cubic root of 20731120 is about 274.7098648032.

Adding to 20731120 its reverse (2113702), we get a palindrome (22844822).

The spelling of 20731120 in words is "twenty million, seven hundred thirty-one thousand, one hundred twenty".