30755561 has 2 divisors, whose sum is σ = 30755562. Its totient is φ = 30755560.

The previous prime is 30755489. The next prime is 30755563. The reversal of 30755561 is 16555703.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 26214400 + 4541161 = 5120^2 + 2131^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-30755561 is a prime.

Together with 30755563, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (30755563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15377780 + 15377781.

It is an arithmetic number, because the mean of its divisors is an integer number (15377781).

Almost surely, 2^30755561 is an apocalyptic number.

It is an amenable number.

30755561 is a deficient number, since it is larger than the sum of its proper divisors (1).

30755561 is an equidigital number, since it uses as much as digits as its factorization.

30755561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15750, while the sum is 32.

The square root of 30755561 is about 5545.7696490208. The cubic root of 30755561 is about 313.3102124431.

The spelling of 30755561 in words is "thirty million, seven hundred fifty-five thousand, five hundred sixty-one".