61691347779331 has 2 divisors, whose sum is σ = 61691347779332. Its totient is φ = 61691347779330.

The previous prime is 61691347779317. The next prime is 61691347779353. The reversal of 61691347779331 is 13397774319616.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 61691347779331 - 2¹⁵ = 61691347746563 is a prime.

It is a super-2 number, since 2×61691347779331² (a number of 28 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (61691347773331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30845673889665 + 30845673889666.

It is an arithmetic number, because the mean of its divisors is an integer number (30845673889666).

Almost surely, 2^{61691347779331} is an apocalyptic number.

61691347779331 is a deficient number, since it is larger than the sum of its proper divisors (1).

61691347779331 is an equidigital number, since it uses as much as digits as its factorization.

61691347779331 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108020304, while the sum is 67.

The spelling of 61691347779331 in words is "sixty-one trillion, six hundred ninety-one billion, three hundred forty-seven million, seven hundred seventy-nine thousand, three hundred thirty-one".