133171997 has 4 divisors (see below), whose sum is σ = 152196576. Its totient is φ = 114147420.

The previous prime is 133171937. The next prime is 133172071. The reversal of 133171997 is 799171331.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 133171997 - 2⁶ = 133171933 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133171937) 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, 9512279 + ... + 9512292.

It is an arithmetic number, because the mean of its divisors is an integer number (38049144).

Almost surely, 2^133171997 is an apocalyptic number.

It is an amenable number.

133171997 is a deficient number, since it is larger than the sum of its proper divisors (19024579).

133171997 is an equidigital number, since it uses as much as digits as its factorization.

133171997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19024578.

The product of its digits is 35721, while the sum is 41.

The square root of 133171997 is about 11540.0172010270. The cubic root of 133171997 is about 510.6668158390. Note that the first 3 decimals are identical.

The spelling of 133171997 in words is "one hundred thirty-three million, one hundred seventy-one thousand, nine hundred ninety-seven".