91208138007 has 64 divisors (see below), whose sum is σ = 147538427904. Its totient is φ = 49031775360.

The previous prime is 91208137981. The next prime is 91208138057. The reversal of 91208138007 is 70083180219.

It is not a de Polignac number, because 91208138007 - 2¹¹ = 91208135959 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91208138057) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3016032 + ... + 3046122.

It is an arithmetic number, because the mean of its divisors is an integer number (2305287936).

Almost surely, 2^91208138007 is an apocalyptic number.

91208138007 is a deficient number, since it is larger than the sum of its proper divisors (56330289897).

91208138007 is a wasteful number, since it uses less digits than its factorization.

91208138007 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30268.

The product of its (nonzero) digits is 24192, while the sum is 39.

The spelling of 91208138007 in words is "ninety-one billion, two hundred eight million, one hundred thirty-eight thousand, seven".