30936881 has 4 divisors (see below), whose sum is σ = 32003700. Its totient is φ = 29870064.

The previous prime is 30936859. The next prime is 30936887. The reversal of 30936881 is 18863903.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 9859600 + 21077281 = 3140^2 + 4591^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-30936881 is a prime.

It is a super-2 number, since 2×30936881² = 1914181212016322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (30936887) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 533366 + ... + 533423.

It is an arithmetic number, because the mean of its divisors is an integer number (8000925).

Almost surely, 2^30936881 is an apocalyptic number.

It is an amenable number.

30936881 is a deficient number, since it is larger than the sum of its proper divisors (1066819).

30936881 is a wasteful number, since it uses less digits than its factorization.

30936881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1066818.

The product of its (nonzero) digits is 31104, while the sum is 38.

The square root of 30936881 is about 5562.0932210814. The cubic root of 30936881 is about 313.9247152060.

The spelling of 30936881 in words is "thirty million, nine hundred thirty-six thousand, eight hundred eighty-one".