30797981 has 4 divisors (see below), whose sum is σ = 30932700. Its totient is φ = 30663264.

The previous prime is 30797959. The next prime is 30798013. The reversal of 30797981 is 18979703.

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 26429881 + 4368100 = 5141^2 + 2090^2 .

It is a cyclic number.

It is not a de Polignac number, because 30797981 - 2¹⁰ = 30796957 is a prime.

It is a super-2 number, since 2×30797981² = 1897031267352722, 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 (30797381) 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, 67016 + ... + 67473.

It is an arithmetic number, because the mean of its divisors is an integer number (7733175).

Almost surely, 2^30797981 is an apocalyptic number.

It is an amenable number.

30797981 is a deficient number, since it is larger than the sum of its proper divisors (134719).

30797981 is a wasteful number, since it uses less digits than its factorization.

30797981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134718.

The product of its (nonzero) digits is 95256, while the sum is 44.

The square root of 30797981 is about 5549.5928679499. The cubic root of 30797981 is about 313.4541919712.

The spelling of 30797981 in words is "thirty million, seven hundred ninety-seven thousand, nine hundred eighty-one".