133640631 has 8 divisors (see below), whose sum is σ = 197986160. Its totient is φ = 89093736.

The previous prime is 133640609. The next prime is 133640651. The reversal of 133640631 is 136046331.

133640631 is a `hidden beast` number, since 13 + 3 + 640 + 6 + 3 + 1 = 666.

It is not a de Polignac number, because 133640631 - 2⁷ = 133640503 is a prime.

It is a super-2 number, since 2×133640631² = 35719636508156322, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 4949653 = 133640631 / (1 + 3 + 3 + 6 + 4 + 0 + 6 + 3 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 133640595 and 133640604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133640651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2474800 + ... + 2474853.

It is an arithmetic number, because the mean of its divisors is an integer number (24748270).

Almost surely, 2^133640631 is an apocalyptic number.

133640631 is a deficient number, since it is larger than the sum of its proper divisors (64345529).

133640631 is an equidigital number, since it uses as much as digits as its factorization.

133640631 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4949662 (or 4949656 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 27.

The square root of 133640631 is about 11560.3041049965. The cubic root of 133640631 is about 511.2651289653.

Adding to 133640631 its reverse (136046331), we get a palindrome (269686962).

The spelling of 133640631 in words is "one hundred thirty-three million, six hundred forty thousand, six hundred thirty-one".