61908857693 has 2 divisors, whose sum is σ = 61908857694. Its totient is φ = 61908857692.

The previous prime is 61908857683. The next prime is 61908857701. The reversal of 61908857693 is 39675880916.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 44176473124 + 17732384569 = 210182^2 + 133163^2 .

It is a cyclic number.

It is not a de Polignac number, because 61908857693 - 2²⁴ = 61892080477 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61908857683) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30954428846 + 30954428847.

It is an arithmetic number, because the mean of its divisors is an integer number (30954428847).

Almost surely, 2^61908857693 is an apocalyptic number.

It is an amenable number.

61908857693 is a deficient number, since it is larger than the sum of its proper divisors (1).

61908857693 is an equidigital number, since it uses as much as digits as its factorization.

61908857693 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 19595520, while the sum is 62.

The spelling of 61908857693 in words is "sixty-one billion, nine hundred eight million, eight hundred fifty-seven thousand, six hundred ninety-three".