61561307 has 2 divisors, whose sum is σ = 61561308. Its totient is φ = 61561306.

The previous prime is 61561289. The next prime is 61561321. The reversal of 61561307 is 70316516.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 61561307 - 2⁶ = 61561243 is a prime.

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 61561307.

It is not a weakly prime, because it can be changed into another prime (61561327) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30780653 + 30780654.

It is an arithmetic number, because the mean of its divisors is an integer number (30780654).

Almost surely, 2^61561307 is an apocalyptic number.

61561307 is a deficient number, since it is larger than the sum of its proper divisors (1).

61561307 is an equidigital number, since it uses as much as digits as its factorization.

61561307 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3780, while the sum is 29.

The square root of 61561307 is about 7846.1013885878. The cubic root of 61561307 is about 394.8534562948.

The spelling of 61561307 in words is "sixty-one million, five hundred sixty-one thousand, three hundred seven".