61273720191 has 8 divisors (see below), whose sum is σ = 83598254080. Its totient is φ = 39899166552.

The previous prime is 61273720159. The next prime is 61273720201. The reversal of 61273720191 is 19102737216.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 61273720191 - 2⁵ = 61273720159 is a prime.

It is a super-2 number, since 2×61273720191² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61273720591) 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 in 7 ways as a sum of consecutive naturals, for example, 237494911 + ... + 237495168.

It is an arithmetic number, because the mean of its divisors is an integer number (10449781760).

Almost surely, 2^61273720191 is an apocalyptic number.

61273720191 is a deficient number, since it is larger than the sum of its proper divisors (22324533889).

61273720191 is a wasteful number, since it uses less digits than its factorization.

61273720191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 474990125.

The product of its (nonzero) digits is 31752, while the sum is 39.

The spelling of 61273720191 in words is "sixty-one billion, two hundred seventy-three million, seven hundred twenty thousand, one hundred ninety-one".