30731969 has 4 divisors (see below), whose sum is σ = 30891396. Its totient is φ = 30572544.

The previous prime is 30731963. The next prime is 30731989. The reversal of 30731969 is 96913703.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 96913703 = 2887 ⋅33569.

It can be written as a sum of positive squares in 2 ways, for example, as 14531344 + 16200625 = 3812^2 + 4025^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-30731969 is a prime.

It is a super-2 number, since 2×30731969² = 1888907837233922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (30731963) 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, 79424 + ... + 79809.

It is an arithmetic number, because the mean of its divisors is an integer number (7722849).

Almost surely, 2^30731969 is an apocalyptic number.

It is an amenable number.

30731969 is a deficient number, since it is larger than the sum of its proper divisors (159427).

30731969 is a wasteful number, since it uses less digits than its factorization.

30731969 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159426.

The product of its (nonzero) digits is 30618, while the sum is 38.

The square root of 30731969 is about 5543.6422142848. The cubic root of 30731969 is about 313.2300805354.

The spelling of 30731969 in words is "thirty million, seven hundred thirty-one thousand, nine hundred sixty-nine".