30981744 has 80 divisors (see below), whose sum is σ = 92032800. Its totient is φ = 9967104.

The previous prime is 30981737. The next prime is 30981749. The reversal of 30981744 is 44718903.

It is a happy number.

It is a super-2 number, since 2×30981744² = 1919736922563072, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 30981699 and 30981708.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30981749) 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, 11292 + ... + 13764.

It is an arithmetic number, because the mean of its divisors is an integer number (1150410).

Almost surely, 2^30981744 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 30981744, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46016400).

30981744 is an abundant number, since it is smaller than the sum of its proper divisors (61051056).

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

30981744 is a wasteful number, since it uses less digits than its factorization.

30981744 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2519 (or 2507 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 30981744 is about 5566.1246841946. The cubic root of 30981744 is about 314.0763874902.

The spelling of 30981744 in words is "thirty million, nine hundred eighty-one thousand, seven hundred forty-four".