61513500409 has 2 divisors, whose sum is σ = 61513500410. Its totient is φ = 61513500408.

The previous prime is 61513500397. The next prime is 61513500427. The reversal of 61513500409 is 90400531516.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 55978140409 + 5535360000 = 236597^2 + 74400^2 .

It is a cyclic number.

It is not a de Polignac number, because 61513500409 - 2²⁵ = 61479945977 is a prime.

It is not a weakly prime, because it can be changed into another prime (61513500479) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30756750204 + 30756750205.

It is an arithmetic number, because the mean of its divisors is an integer number (30756750205).

Almost surely, 2^61513500409 is an apocalyptic number.

It is an amenable number.

61513500409 is a deficient number, since it is larger than the sum of its proper divisors (1).

61513500409 is an equidigital number, since it uses as much as digits as its factorization.

61513500409 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16200, while the sum is 34.

The spelling of 61513500409 in words is "sixty-one billion, five hundred thirteen million, five hundred thousand, four hundred nine".