20717312 has 72 divisors (see below), whose sum is σ = 51606912. Its totient is φ = 8064000.

The previous prime is 20717261. The next prime is 20717377. The reversal of 20717312 is 21371702.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19187 + ... + 20237.

Almost surely, 2^20717312 is an apocalyptic number.

20717312 is a gapful number since it is divisible by the number (22) 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 20717312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25803456).

20717312 is an abundant number, since it is smaller than the sum of its proper divisors (30889600).

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

20717312 is a wasteful number, since it uses less digits than its factorization.

20717312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1085 (or 1071 counting only the distinct ones).

The product of its (nonzero) digits is 588, while the sum is 23.

The square root of 20717312 is about 4551.6274012709. The cubic root of 20717312 is about 274.6488609230.

The spelling of 20717312 in words is "twenty million, seven hundred seventeen thousand, three hundred twelve".