91138605 has 16 divisors (see below), whose sum is σ = 150526464. Its totient is φ = 47039040.

The previous prime is 91138603. The next prime is 91138631. The reversal of 91138605 is 50683119.

It is not a de Polignac number, because 91138605 - 2¹ = 91138603 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91138601) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 97534 + ... + 98463.

It is an arithmetic number, because the mean of its divisors is an integer number (9407904).

Almost surely, 2^91138605 is an apocalyptic number.

It is an amenable number.

91138605 is a deficient number, since it is larger than the sum of its proper divisors (59387859).

91138605 is a wasteful number, since it uses less digits than its factorization.

91138605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 196036.

The product of its (nonzero) digits is 6480, while the sum is 33.

The square root of 91138605 is about 9546.6541259229. The cubic root of 91138605 is about 450.0223939473.

The spelling of 91138605 in words is "ninety-one million, one hundred thirty-eight thousand, six hundred five".