91004788949 has 2 divisors, whose sum is σ = 91004788950. Its totient is φ = 91004788948.

The previous prime is 91004788883. The next prime is 91004788951. The reversal of 91004788949 is 94988740019.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 91004788900 + 49 = 301670^2 + 7^2 .

It is an emirp because it is prime and its reverse (94988740019) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91004788949 - 2¹⁶ = 91004723413 is a prime.

It is a super-2 number, since 2×91004788949² (a number of 23 digits) contains 22 as substring.

It is a Sophie Germain prime.

Together with 91004788951, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91004788969) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45502394474 + 45502394475.

It is an arithmetic number, because the mean of its divisors is an integer number (45502394475).

Almost surely, 2^91004788949 is an apocalyptic number.

It is an amenable number.

91004788949 is a deficient number, since it is larger than the sum of its proper divisors (1).

91004788949 is an equidigital number, since it uses as much as digits as its factorization.

91004788949 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5225472, while the sum is 59.

It can be divided in two parts, 910047889 and 49, that multiplied together give a square (44592346561 = 211169²).

The spelling of 91004788949 in words is "ninety-one billion, four million, seven hundred eighty-eight thousand, nine hundred forty-nine".