30551561 has 2 divisors, whose sum is σ = 30551562. Its totient is φ = 30551560.

The previous prime is 30551503. The next prime is 30551597. The reversal of 30551561 is 16515503.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27510025 + 3041536 = 5245^2 + 1744^2 .

It is a cyclic number.

It is not a de Polignac number, because 30551561 - 2⁶ = 30551497 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 30551561.

It is not a weakly prime, because it can be changed into another prime (30550561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15275780 + 15275781.

It is an arithmetic number, because the mean of its divisors is an integer number (15275781).

Almost surely, 2^30551561 is an apocalyptic number.

It is an amenable number.

30551561 is a deficient number, since it is larger than the sum of its proper divisors (1).

30551561 is an equidigital number, since it uses as much as digits as its factorization.

30551561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2250, while the sum is 26.

The square root of 30551561 is about 5527.3466509710. The cubic root of 30551561 is about 312.6159518512.

The spelling of 30551561 in words is "thirty million, five hundred fifty-one thousand, five hundred sixty-one".