30391812 has 54 divisors (see below), whose sum is σ = 84454734. Its totient is φ = 9208320.

The previous prime is 30391799. The next prime is 30391813. The reversal of 30391812 is 21819303.

It can be written as a sum of positive squares in only one way, i.e., 21958596 + 8433216 = 4686^2 + 2904^2 .

It is not an unprimeable number, because it can be changed into a prime (30391813) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 868 + ... + 7844.

Almost surely, 2^30391812 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 30391812, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42227367).

30391812 is an abundant number, since it is smaller than the sum of its proper divisors (54062922).

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

30391812 is a wasteful number, since it uses less digits than its factorization.

30391812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7009 (or 6993 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 30391812 is about 5512.8769258891. The cubic root of 30391812 is about 312.0701272346.

It can be divided in two parts, 3039 and 1812, that added together give a triangular number (4851 = T₉₈).

The spelling of 30391812 in words is "thirty million, three hundred ninety-one thousand, eight hundred twelve".