91138806 has 24 divisors (see below), whose sum is σ = 215419464. Its totient is φ = 27617760.

The previous prime is 91138799. The next prime is 91138813. The reversal of 91138806 is 60883119.

It is an interprime number because it is at equal distance from previous prime (91138799) and next prime (91138813).

It is a congruent number.

It is an unprimeable number.

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 in 11 ways as a sum of consecutive naturals, for example, 229951 + ... + 230346.

It is an arithmetic number, because the mean of its divisors is an integer number (8975811).

Almost surely, 2^91138806 is an apocalyptic number.

91138806 is an abundant number, since it is smaller than the sum of its proper divisors (124280658).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91138806 is a wasteful number, since it uses less digits than its factorization.

91138806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 460316 (or 460313 counting only the distinct ones).

The product of its (nonzero) digits is 10368, while the sum is 36.

The square root of 91138806 is about 9546.6646531655. The cubic root of 91138806 is about 450.0227247783.

The spelling of 91138806 in words is "ninety-one million, one hundred thirty-eight thousand, eight hundred six".