133431213 has 16 divisors (see below), whose sum is σ = 183051776. Its totient is φ = 86391360.

The previous prime is 133431197. The next prime is 133431227. The reversal of 133431213 is 312134331.

It is not a de Polignac number, because 133431213 - 2⁴ = 133431197 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 133431213.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133431293) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 109395 + ... + 110607.

It is an arithmetic number, because the mean of its divisors is an integer number (11440736).

Almost surely, 2^133431213 is an apocalyptic number.

It is an amenable number.

133431213 is a deficient number, since it is larger than the sum of its proper divisors (49620563).

133431213 is a wasteful number, since it uses less digits than its factorization.

133431213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2244.

The product of its digits is 648, while the sum is 21.

The square root of 133431213 is about 11551.2429201363. The cubic root of 133431213 is about 510.9979345380.

Adding to 133431213 its reverse (312134331), we get a palindrome (445565544).

The spelling of 133431213 in words is "one hundred thirty-three million, four hundred thirty-one thousand, two hundred thirteen".