91139040 has 288 divisors, whose sum is σ = 343496160. Its totient is φ = 22560768.

The previous prime is 91139033. The next prime is 91139071. The reversal of 91139040 is 4093119.

It is a tau number, because it is divible by the number of its divisors (288).

It is a super-2 number, since 2×91139040² = 16612649224243200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 91138995 and 91139013.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1248444 + ... + 1248516.

It is an arithmetic number, because the mean of its divisors is an integer number (1192695).

Almost surely, 2^91139040 is an apocalyptic number.

91139040 is a gapful number since it is divisible by the number (90) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91139040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (171748080).

91139040 is an abundant number, since it is smaller than the sum of its proper divisors (252357120).

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

91139040 is a wasteful number, since it uses less digits than its factorization.

91139040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131 (or 100 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 91139040 is about 9546.6769087468. The cubic root of 91139040 is about 450.0231099243.

The spelling of 91139040 in words is "ninety-one million, one hundred thirty-nine thousand, forty".