91178917051 has 2 divisors, whose sum is σ = 91178917052. Its totient is φ = 91178917050.

The previous prime is 91178917003. The next prime is 91178917103. The reversal of 91178917051 is 15071987119.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 91178917051 - 2⁹ = 91178916539 is a prime.

It is a super-3 number, since 3×91178917051³ (a number of 34 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 91178916986 and 91178917004.

It is not a weakly prime, because it can be changed into another prime (91178947051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45589458525 + 45589458526.

It is an arithmetic number, because the mean of its divisors is an integer number (45589458526).

Almost surely, 2^91178917051 is an apocalyptic number.

91178917051 is a deficient number, since it is larger than the sum of its proper divisors (1).

91178917051 is an equidigital number, since it uses as much as digits as its factorization.

91178917051 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 158760, while the sum is 49.

The spelling of 91178917051 in words is "ninety-one billion, one hundred seventy-eight million, nine hundred seventeen thousand, fifty-one".