133431431 has 4 divisors (see below), whose sum is σ = 152493072. Its totient is φ = 114369792.

The previous prime is 133431413. The next prime is 133431439. The reversal of 133431431 is 134134331.

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 133431431 - 2⁶ = 133431367 is a prime.

It is a super-2 number, since 2×133431431² = 35607893557415522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 133431397 and 133431406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133431439) 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, 9530810 + ... + 9530823.

It is an arithmetic number, because the mean of its divisors is an integer number (38123268).

Almost surely, 2^133431431 is an apocalyptic number.

133431431 is a deficient number, since it is larger than the sum of its proper divisors (19061641).

133431431 is an equidigital number, since it uses as much as digits as its factorization.

133431431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19061640.

The product of its digits is 1296, while the sum is 23.

The square root of 133431431 is about 11551.2523563465. The cubic root of 133431431 is about 510.9982128274.

Adding to 133431431 its reverse (134134331), we get a palindrome (267565762).

The spelling of 133431431 in words is "one hundred thirty-three million, four hundred thirty-one thousand, four hundred thirty-one".