91026748957 has 4 divisors (see below), whose sum is σ = 91069830460. Its totient is φ = 90983667456.

The previous prime is 91026748913. The next prime is 91026748961. The reversal of 91026748957 is 75984762019.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 28915642116 + 62111106841 = 170046^2 + 249221^2 .

It is a cyclic number.

It is not a de Polignac number, because 91026748957 - 2¹⁹ = 91026224669 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91026748157) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21537582 + ... + 21541807.

It is an arithmetic number, because the mean of its divisors is an integer number (22767457615).

Almost surely, 2^91026748957 is an apocalyptic number.

It is an amenable number.

91026748957 is a deficient number, since it is larger than the sum of its proper divisors (43081503).

91026748957 is a wasteful number, since it uses less digits than its factorization.

91026748957 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43081502.

The product of its (nonzero) digits is 7620480, while the sum is 58.

The spelling of 91026748957 in words is "ninety-one billion, twenty-six million, seven hundred forty-eight thousand, nine hundred fifty-seven".