30997765 has 4 divisors (see below), whose sum is σ = 37197324. Its totient is φ = 24798208.

The previous prime is 30997741. The next prime is 30997787. The reversal of 30997765 is 56779903.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56779903 = 1459 ⋅38917.

It can be written as a sum of positive squares in 2 ways, for example, as 23804641 + 7193124 = 4879^2 + 2682^2 .

It is a cyclic number.

It is not a de Polignac number, because 30997765 - 2¹¹ = 30995717 is a prime.

It is a super-2 number, since 2×30997765² = 1921722869990450, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3099772 + ... + 3099781.

It is an arithmetic number, because the mean of its divisors is an integer number (9299331).

Almost surely, 2^30997765 is an apocalyptic number.

It is an amenable number.

30997765 is a deficient number, since it is larger than the sum of its proper divisors (6199559).

30997765 is an equidigital number, since it uses as much as digits as its factorization.

30997765 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6199558.

The product of its (nonzero) digits is 357210, while the sum is 46.

The square root of 30997765 is about 5567.5636502873. The cubic root of 30997765 is about 314.1305156107.

The spelling of 30997765 in words is "thirty million, nine hundred ninety-seven thousand, seven hundred sixty-five".