91099474649 has 2 divisors, whose sum is σ = 91099474650. Its totient is φ = 91099474648.

The previous prime is 91099474643. The next prime is 91099474663. The reversal of 91099474649 is 94647499019.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 77930305600 + 13169169049 = 279160^2 + 114757^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91099474649 is a prime.

It is a super-2 number, since 2×91099474649² (a number of 23 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 91099474591 and 91099474600.

It is not a weakly prime, because it can be changed into another prime (91099474643) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45549737324 + 45549737325.

It is an arithmetic number, because the mean of its divisors is an integer number (45549737325).

Almost surely, 2^91099474649 is an apocalyptic number.

It is an amenable number.

91099474649 is a deficient number, since it is larger than the sum of its proper divisors (1).

91099474649 is an equidigital number, since it uses as much as digits as its factorization.

91099474649 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17635968, while the sum is 62.

The spelling of 91099474649 in words is "ninety-one billion, ninety-nine million, four hundred seventy-four thousand, six hundred forty-nine".