30972839 has 4 divisors (see below), whose sum is σ = 31050480. Its totient is φ = 30895200.

The previous prime is 30972797. The next prime is 30972847. The reversal of 30972839 is 93827903.

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

It is a cyclic number.

It is not a de Polignac number, because 30972839 - 2²⁰ = 29924263 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 30972796 and 30972805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30972889) 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, 38219 + ... + 39020.

It is an arithmetic number, because the mean of its divisors is an integer number (7762620).

Almost surely, 2^30972839 is an apocalyptic number.

30972839 is a deficient number, since it is larger than the sum of its proper divisors (77641).

30972839 is an equidigital number, since it uses as much as digits as its factorization.

30972839 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 77640.

The product of its (nonzero) digits is 81648, while the sum is 41.

The square root of 30972839 is about 5565.3246985239. The cubic root of 30972839 is about 314.0462932274.

The spelling of 30972839 in words is "thirty million, nine hundred seventy-two thousand, eight hundred thirty-nine".