20731812 has 48 divisors (see below), whose sum is σ = 51609600. Its totient is φ = 6458400.

The previous prime is 20731811. The next prime is 20731813. The reversal of 20731812 is 21813702.

It is an interprime number because it is at equal distance from previous prime (20731811) and next prime (20731813).

It is not an unprimeable number, because it can be changed into a prime (20731811) 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, 17437 + ... + 18587.

It is an arithmetic number, because the mean of its divisors is an integer number (1075200).

Almost surely, 2^20731812 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20731812, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25804800).

20731812 is an abundant number, since it is smaller than the sum of its proper divisors (30877788).

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

20731812 is a wasteful number, since it uses less digits than its factorization.

20731812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1256 (or 1254 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 24.

The square root of 20731812 is about 4553.2199595451. The cubic root of 20731812 is about 274.7129213531.

The spelling of 20731812 in words is "twenty million, seven hundred thirty-one thousand, eight hundred twelve".