61245408557 has 2 divisors, whose sum is σ = 61245408558. Its totient is φ = 61245408556.

The previous prime is 61245408503. The next prime is 61245408577. The reversal of 61245408557 is 75580454216.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 47060360356 + 14185048201 = 216934^2 + 119101^2 .

It is a cyclic number.

It is not a de Polignac number, because 61245408557 - 2³⁰ = 60171666733 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61245408577) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30622704278 + 30622704279.

It is an arithmetic number, because the mean of its divisors is an integer number (30622704279).

Almost surely, 2^61245408557 is an apocalyptic number.

It is an amenable number.

61245408557 is a deficient number, since it is larger than the sum of its proper divisors (1).

61245408557 is an equidigital number, since it uses as much as digits as its factorization.

61245408557 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1344000, while the sum is 47.

The spelling of 61245408557 in words is "sixty-one billion, two hundred forty-five million, four hundred eight thousand, five hundred fifty-seven".