91868620577 has 2 divisors, whose sum is σ = 91868620578. Its totient is φ = 91868620576.

The previous prime is 91868620531. The next prime is 91868620589. The reversal of 91868620577 is 77502686819.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68058896161 + 23809724416 = 260881^2 + 154304^2 .

It is a cyclic number.

It is not a de Polignac number, because 91868620577 - 2¹² = 91868616481 is a prime.

It is a super-3 number, since 3×91868620577³ (a number of 34 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (91868625577) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45934310288 + 45934310289.

It is an arithmetic number, because the mean of its divisors is an integer number (45934310289).

Almost surely, 2^91868620577 is an apocalyptic number.

It is an amenable number.

91868620577 is a deficient number, since it is larger than the sum of its proper divisors (1).

91868620577 is an equidigital number, since it uses as much as digits as its factorization.

91868620577 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 10160640, while the sum is 59.

The spelling of 91868620577 in words is "ninety-one billion, eight hundred sixty-eight million, six hundred twenty thousand, five hundred seventy-seven".