91667751761 has 4 divisors (see below), whose sum is σ = 91672653492. Its totient is φ = 91662850032.

The previous prime is 91667751739. The next prime is 91667751779. The reversal of 91667751761 is 16715776619.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16715776619 = 61961 ⋅269779.

It can be written as a sum of positive squares in 2 ways, for example, as 44994470161 + 46673281600 = 212119^2 + 216040^2 .

It is a cyclic number.

It is not a de Polignac number, because 91667751761 - 2¹⁴ = 91667735377 is a prime.

It is a super-2 number, since 2×91667751761² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 91667751697 and 91667751706.

It is not an unprimeable number, because it can be changed into a prime (91667759761) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2422706 + ... + 2460251.

It is an arithmetic number, because the mean of its divisors is an integer number (22918163373).

Almost surely, 2^91667751761 is an apocalyptic number.

It is an amenable number.

91667751761 is a deficient number, since it is larger than the sum of its proper divisors (4901731).

91667751761 is a wasteful number, since it uses less digits than its factorization.

91667751761 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4901730.

The product of its digits is 3333960, while the sum is 56.

The spelling of 91667751761 in words is "ninety-one billion, six hundred sixty-seven million, seven hundred fifty-one thousand, seven hundred sixty-one".