30991245 has 8 divisors (see below), whose sum is σ = 49586016. Its totient is φ = 16528656.

The previous prime is 30991243. The next prime is 30991249. The reversal of 30991245 is 54219903.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 30991245 - 2¹ = 30991243 is a prime.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30991243) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1033027 + ... + 1033056.

It is an arithmetic number, because the mean of its divisors is an integer number (6198252).

Almost surely, 2^30991245 is an apocalyptic number.

It is an amenable number.

30991245 is a deficient number, since it is larger than the sum of its proper divisors (18594771).

30991245 is a wasteful number, since it uses less digits than its factorization.

30991245 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2066091.

The product of its (nonzero) digits is 9720, while the sum is 33.

The square root of 30991245 is about 5566.9780851015. The cubic root of 30991245 is about 314.1084895648.

The spelling of 30991245 in words is "thirty million, nine hundred ninety-one thousand, two hundred forty-five".