61645260361 has 2 divisors, whose sum is σ = 61645260362. Its totient is φ = 61645260360.

The previous prime is 61645260349. The next prime is 61645260367. The reversal of 61645260361 is 16306254616.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 46723416336 + 14921844025 = 216156^2 + 122155^2 .

It is a cyclic number.

It is not a de Polignac number, because 61645260361 - 2¹⁵ = 61645227593 is a prime.

It is not a weakly prime, because it can be changed into another prime (61645260367) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30822630180 + 30822630181.

It is an arithmetic number, because the mean of its divisors is an integer number (30822630181).

Almost surely, 2^61645260361 is an apocalyptic number.

It is an amenable number.

61645260361 is a deficient number, since it is larger than the sum of its proper divisors (1).

61645260361 is an equidigital number, since it uses as much as digits as its factorization.

61645260361 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 155520, while the sum is 40.

The spelling of 61645260361 in words is "sixty-one billion, six hundred forty-five million, two hundred sixty thousand, three hundred sixty-one".