30511989 has 6 divisors (see below), whose sum is σ = 44072886. Its totient is φ = 20341320.

The previous prime is 30511981. The next prime is 30512003. The reversal of 30511989 is 98911503.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 21762225 + 8749764 = 4665^2 + 2958^2 .

It is not a de Polignac number, because 30511989 - 2³ = 30511981 is a prime.

It is a super-2 number, since 2×30511989² = 1861962945472242, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30511981) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1695102 + ... + 1695119.

It is an arithmetic number, because the mean of its divisors is an integer number (7345481).

Almost surely, 2^30511989 is an apocalyptic number.

It is an amenable number.

30511989 is a deficient number, since it is larger than the sum of its proper divisors (13560897).

30511989 is a wasteful number, since it uses less digits than its factorization.

30511989 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3390227 (or 3390224 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 36.

The square root of 30511989 is about 5523.7658350079. The cubic root of 30511989 is about 312.4809212886.

The spelling of 30511989 in words is "thirty million, five hundred eleven thousand, nine hundred eighty-nine".