61680731911 has 4 divisors (see below), whose sum is σ = 61694919000. Its totient is φ = 61666544824.

The previous prime is 61680731897. The next prime is 61680731941. The reversal of 61680731911 is 11913708616.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 61680731911 - 2²³ = 61672343303 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61680731941) 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 3 ways as a sum of consecutive naturals, for example, 7087021 + ... + 7095718.

It is an arithmetic number, because the mean of its divisors is an integer number (15423729750).

Almost surely, 2^61680731911 is an apocalyptic number.

61680731911 is a deficient number, since it is larger than the sum of its proper divisors (14187089).

61680731911 is a wasteful number, since it uses less digits than its factorization.

61680731911 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14187088.

The product of its (nonzero) digits is 54432, while the sum is 43.

The spelling of 61680731911 in words is "sixty-one billion, six hundred eighty million, seven hundred thirty-one thousand, nine hundred eleven".