30981894 has 16 divisors (see below), whose sum is σ = 65225280. Its totient is φ = 9783720.

The previous prime is 30981877. The next prime is 30981911. The reversal of 30981894 is 49818903.

It is an interprime number because it is at equal distance from previous prime (30981877) and next prime (30981911).

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 135772 + ... + 135999.

It is an arithmetic number, because the mean of its divisors is an integer number (4076580).

Almost surely, 2^30981894 is an apocalyptic number.

30981894 is an abundant number, since it is smaller than the sum of its proper divisors (34243386).

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

30981894 is a wasteful number, since it uses less digits than its factorization.

30981894 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271795.

The product of its (nonzero) digits is 62208, while the sum is 42.

The square root of 30981894 is about 5566.1381585440. The cubic root of 30981894 is about 314.0768943627.

The spelling of 30981894 in words is "thirty million, nine hundred eighty-one thousand, eight hundred ninety-four".