91919181853 has 2 divisors, whose sum is σ = 91919181854. Its totient is φ = 91919181852.

The previous prime is 91919181847. The next prime is 91919181919. The reversal of 91919181853 is 35818191919.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77374098244 + 14545083609 = 278162^2 + 120603^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91919181853 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 91919181794 and 91919181803.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91919181833) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45959590926 + 45959590927.

It is an arithmetic number, because the mean of its divisors is an integer number (45959590927).

Almost surely, 2^91919181853 is an apocalyptic number.

It is an amenable number.

91919181853 is a deficient number, since it is larger than the sum of its proper divisors (1).

91919181853 is an equidigital number, since it uses as much as digits as its factorization.

91919181853 is an evil number, because the sum of its binary digits is even.

The product of its digits is 699840, while the sum is 55.

The spelling of 91919181853 in words is "ninety-one billion, nine hundred nineteen million, one hundred eighty-one thousand, eight hundred fifty-three".