61642518191 has 2 divisors, whose sum is σ = 61642518192. Its totient is φ = 61642518190.

The previous prime is 61642518167. The next prime is 61642518229. The reversal of 61642518191 is 19181524616.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61642518191 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61642518131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30821259095 + 30821259096.

It is an arithmetic number, because the mean of its divisors is an integer number (30821259096).

Almost surely, 2^61642518191 is an apocalyptic number.

61642518191 is a deficient number, since it is larger than the sum of its proper divisors (1).

61642518191 is an equidigital number, since it uses as much as digits as its factorization.

61642518191 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 103680, while the sum is 44.

The spelling of 61642518191 in words is "sixty-one billion, six hundred forty-two million, five hundred eighteen thousand, one hundred ninety-one".