36138591 has 12 divisors (see below), whose sum is σ = 53884480. Its totient is φ = 23315040.

The previous prime is 36138563. The next prime is 36138593. The reversal of 36138591 is 19583163.

It is a happy number.

36138591 is a `hidden beast` number, since 3 + 61 + 3 + 8 + 591 = 666.

It is not a de Polignac number, because 36138591 - 2⁵ = 36138559 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 (36138593) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 64486 + ... + 65043.

Almost surely, 2^36138591 is an apocalyptic number.

36138591 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

36138591 is a deficient number, since it is larger than the sum of its proper divisors (17745889).

36138591 is a wasteful number, since it uses less digits than its factorization.

36138591 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129566 (or 129563 counting only the distinct ones).

The product of its digits is 19440, while the sum is 36.

The square root of 36138591 is about 6011.5381559132. The cubic root of 36138591 is about 330.6159021252.

The spelling of 36138591 in words is "thirty-six million, one hundred thirty-eight thousand, five hundred ninety-one".