30811661 has 2 divisors, whose sum is σ = 30811662. Its totient is φ = 30811660.

The previous prime is 30811643. The next prime is 30811663. The reversal of 30811661 is 16611803.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 29106025 + 1705636 = 5395^2 + 1306^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-30811661 is a prime.

Together with 30811663, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 30811661.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30811663) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15405830 + 15405831.

It is an arithmetic number, because the mean of its divisors is an integer number (15405831).

Almost surely, 2^30811661 is an apocalyptic number.

It is an amenable number.

30811661 is a deficient number, since it is larger than the sum of its proper divisors (1).

30811661 is an equidigital number, since it uses as much as digits as its factorization.

30811661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 26.

The square root of 30811661 is about 5550.8252539600. The cubic root of 30811661 is about 313.5005956473.

The spelling of 30811661 in words is "thirty million, eight hundred eleven thousand, six hundred sixty-one".