30981989 has 16 divisors (see below), whose sum is σ = 35143680. Its totient is φ = 27157680.

The previous prime is 30981967. The next prime is 30982009. The reversal of 30981989 is 98918903.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-30981989 is a prime.

It is a super-2 number, since 2×30981989² = 1919767284792242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30981949) 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, 12404 + ... + 14690.

It is an arithmetic number, because the mean of its divisors is an integer number (2196480).

Almost surely, 2^30981989 is an apocalyptic number.

It is an amenable number.

30981989 is a deficient number, since it is larger than the sum of its proper divisors (4161691).

30981989 is a wasteful number, since it uses less digits than its factorization.

30981989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2360.

The product of its (nonzero) digits is 139968, while the sum is 47.

The square root of 30981989 is about 5566.1466922818. The cubic root of 30981989 is about 314.0772153811.

The spelling of 30981989 in words is "thirty million, nine hundred eighty-one thousand, nine hundred eighty-nine".