30991394 has 32 divisors (see below), whose sum is σ = 56263680. Its totient is φ = 12506832.

The previous prime is 30991381. The next prime is 30991397. The reversal of 30991394 is 49319903.

It is a Harshad number since it is a multiple of its sum of digits (38).

It is not an unprimeable number, because it can be changed into a prime (30991397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 69737 + ... + 70179.

It is an arithmetic number, because the mean of its divisors is an integer number (1758240).

Almost surely, 2^30991394 is an apocalyptic number.

30991394 is a deficient number, since it is larger than the sum of its proper divisors (25272286).

30991394 is a wasteful number, since it uses less digits than its factorization.

30991394 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 734.

The product of its (nonzero) digits is 26244, while the sum is 38.

The square root of 30991394 is about 5566.9914675703. The cubic root of 30991394 is about 314.1089929553.

The spelling of 30991394 in words is "thirty million, nine hundred ninety-one thousand, three hundred ninety-four".