133540431 has 4 divisors (see below), whose sum is σ = 178053912. Its totient is φ = 89026952.

The previous prime is 133540411. The next prime is 133540439. The reversal of 133540431 is 134045331.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 133540431 - 2¹⁰ = 133539407 is a prime.

It is a super-2 number, since 2×133540431² = 35666093423331522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133540439) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22256736 + ... + 22256741.

It is an arithmetic number, because the mean of its divisors is an integer number (44513478).

Almost surely, 2^133540431 is an apocalyptic number.

133540431 is a deficient number, since it is larger than the sum of its proper divisors (44513481).

133540431 is an equidigital number, since it uses as much as digits as its factorization.

133540431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44513480.

The product of its (nonzero) digits is 2160, while the sum is 24.

The square root of 133540431 is about 11555.9694963253. The cubic root of 133540431 is about 511.1373195953.

Adding to 133540431 its reverse (134045331), we get a palindrome (267585762).

The spelling of 133540431 in words is "one hundred thirty-three million, five hundred forty thousand, four hundred thirty-one".