133261921 has 4 divisors (see below), whose sum is σ = 143512852. Its totient is φ = 123010992.

The previous prime is 133261913. The next prime is 133261937. The reversal of 133261921 is 129162331.

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

It can be written as a sum of positive squares in 2 ways, for example, as 46771921 + 86490000 = 6839^2 + 9300^2 .

It is not a de Polignac number, because 133261921 - 2³ = 133261913 is a prime.

It is a super-2 number, since 2×133261921² = 35517479177220482, which contains 22 as substring.

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 133261921.

It is not an unprimeable number, because it can be changed into a prime (133261621) 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, 5125446 + ... + 5125471.

It is an arithmetic number, because the mean of its divisors is an integer number (35878213).

Almost surely, 2^133261921 is an apocalyptic number.

It is an amenable number.

133261921 is a deficient number, since it is larger than the sum of its proper divisors (10250931).

133261921 is a wasteful number, since it uses less digits than its factorization.

133261921 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10250930.

The product of its digits is 1944, while the sum is 28.

The square root of 133261921 is about 11543.9127248953. The cubic root of 133261921 is about 510.7817320666.

The spelling of 133261921 in words is "one hundred thirty-three million, two hundred sixty-one thousand, nine hundred twenty-one".