20731248 has 80 divisors (see below), whose sum is σ = 61161760. Its totient is φ = 6718464.

The previous prime is 20731247. The next prime is 20731253. The reversal of 20731248 is 84213702.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20731241) 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, 15336 + ... + 16632.

It is an arithmetic number, because the mean of its divisors is an integer number (764522).

Almost surely, 2^20731248 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 20731248, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30580880).

20731248 is an abundant number, since it is smaller than the sum of its proper divisors (40430512).

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

20731248 is a wasteful number, since it uses less digits than its factorization.

20731248 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1351 (or 1339 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 20731248 is about 4553.1580249317. The cubic root of 20731248 is about 274.7104301817.

It can be divided in two parts, 2073 and 1248, that added together give a triangular number (3321 = T₈₁).

The spelling of 20731248 in words is "twenty million, seven hundred thirty-one thousand, two hundred forty-eight".