133185537 has 6 divisors (see below), whose sum is σ = 192379122. Its totient is φ = 88790352.

The previous prime is 133185469. The next prime is 133185601. The reversal of 133185537 is 735581331.

It is a happy number.

133185537 is a `hidden beast` number, since 13 + 31 + 85 + 537 = 666.

It can be written as a sum of positive squares in only one way, i.e., 92621376 + 40564161 = 9624^2 + 6369^2 .

It is not a de Polignac number, because 133185537 - 2¹¹ = 133183489 is a prime.

It is not an unprimeable number, because it can be changed into a prime (133185337) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 7399188 + ... + 7399205.

It is an arithmetic number, because the mean of its divisors is an integer number (32063187).

It is a Proth number, since it is equal to 8129 ⋅ 2¹⁴ + 1 and 8129 < 2¹⁴.

Almost surely, 2^133185537 is an apocalyptic number.

It is an amenable number.

133185537 is a deficient number, since it is larger than the sum of its proper divisors (59193585).

133185537 is a wasteful number, since it uses less digits than its factorization.

133185537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14798399 (or 14798396 counting only the distinct ones).

The product of its digits is 37800, while the sum is 36.

The square root of 133185537 is about 11540.6038403543. The cubic root of 133185537 is about 510.6841222661.

It can be divided in two parts, 1331 and 85537, that added together give a palindrome (86868).

The spelling of 133185537 in words is "one hundred thirty-three million, one hundred eighty-five thousand, five hundred thirty-seven".