91006775 has 12 divisors (see below), whose sum is σ = 113664600. Its totient is φ = 72278880.

The previous prime is 91006759. The next prime is 91006787. The reversal of 91006775 is 57760019.

91006775 = 428² + 429² + ... + 705².

It is not a de Polignac number, because 91006775 - 2⁴ = 91006759 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9620 + ... + 16569.

It is an arithmetic number, because the mean of its divisors is an integer number (9472050).

Almost surely, 2^91006775 is an apocalyptic number.

91006775 is a deficient number, since it is larger than the sum of its proper divisors (22657825).

91006775 is a wasteful number, since it uses less digits than its factorization.

91006775 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26338 (or 26333 counting only the distinct ones).

The product of its (nonzero) digits is 13230, while the sum is 35.

The square root of 91006775 is about 9539.7471140487. The cubic root of 91006775 is about 449.8053067243.

Subtracting from 91006775 its reverse (57760019), we obtain a square (33246756 = 5766²).

The spelling of 91006775 in words is "ninety-one million, six thousand, seven hundred seventy-five".