133221001 has 4 divisors (see below), whose sum is σ = 133458192. Its totient is φ = 132983812.

The previous prime is 133220987. The next prime is 133221017. The reversal of 133221001 is 100122331.

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, and also an emirpimes, since its reverse is a distinct semiprime: 100122331 = 661 ⋅151471.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-133221001 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (133221031) 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, 117751 + ... + 118876.

It is an arithmetic number, because the mean of its divisors is an integer number (33364548).

Almost surely, 2^133221001 is an apocalyptic number.

It is an amenable number.

133221001 is a deficient number, since it is larger than the sum of its proper divisors (237191).

133221001 is an equidigital number, since it uses as much as digits as its factorization.

133221001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237190.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 133221001 is about 11542.1402261452. The cubic root of 133221001 is about 510.7294457420.

Adding to 133221001 its reverse (100122331), we get a palindrome (233343332).

The spelling of 133221001 in words is "one hundred thirty-three million, two hundred twenty-one thousand, one".