133331021 has 4 divisors (see below), whose sum is σ = 133765632. Its totient is φ = 132896412.

The previous prime is 133330997. The next prime is 133331041. The reversal of 133331021 is 120133331.

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 a de Polignac number, because none of the positive numbers 2^k-133331021 is a prime.

It is a super-2 number, since 2×133331021² = 35554322321804882, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133331041) 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, 216845 + ... + 217458.

It is an arithmetic number, because the mean of its divisors is an integer number (33441408).

Almost surely, 2^133331021 is an apocalyptic number.

It is an amenable number.

133331021 is a deficient number, since it is larger than the sum of its proper divisors (434611).

133331021 is an equidigital number, since it uses as much as digits as its factorization.

133331021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 434610.

The product of its (nonzero) digits is 162, while the sum is 17.

The square root of 133331021 is about 11546.9052563880. The cubic root of 133331021 is about 510.8700016406.

Adding to 133331021 its reverse (120133331), we get a palindrome (253464352).

It can be divided in two parts, 1333310 and 21, that added together give a palindrome (1333331).

The spelling of 133331021 in words is "one hundred thirty-three million, three hundred thirty-one thousand, twenty-one".