30736720 has 60 divisors (see below), whose sum is σ = 83140884. Its totient is φ = 10536960.

The previous prime is 30736711. The next prime is 30736721. The reversal of 30736720 is 2763703.

30736720 is a nontrivial binomial coefficient, being equal to C(7841, 2).

It can be written as a sum of positive squares in 2 ways, for example, as 10916416 + 19820304 = 3304^2 + 4452^2 .

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30736721) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1 + ... + 7840.

Almost surely, 2^30736720 is an apocalyptic number.

30736720 is the 7840-th triangular number.

30736720 is the 2614-th centered nonagonal number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 30736720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41570442).

30736720 is an abundant number, since it is smaller than the sum of its proper divisors (52404164).

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

30736720 is a wasteful number, since it uses less digits than its factorization.

30736720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7868 (or 7855 counting only the distinct ones).

The product of its (nonzero) digits is 5292, while the sum is 28.

The square root of 30736720 is about 5544.0707066198. The cubic root of 30736720 is about 313.2462209421.

The spelling of 30736720 in words is "thirty million, seven hundred thirty-six thousand, seven hundred twenty".