133120021 has 4 divisors (see below), whose sum is σ = 138907872. Its totient is φ = 127332172.

The previous prime is 133120019. The next prime is 133120037. The reversal of 133120021 is 120021331.

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: 120021331 = 2459 ⋅48809.

It is a cyclic number.

It is not a de Polignac number, because 133120021 - 2¹ = 133120019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 133119983 and 133120010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133120051) 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, 2893891 + ... + 2893936.

It is an arithmetic number, because the mean of its divisors is an integer number (34726968).

Almost surely, 2^133120021 is an apocalyptic number.

It is an amenable number.

133120021 is a deficient number, since it is larger than the sum of its proper divisors (5787851).

133120021 is an equidigital number, since it uses as much as digits as its factorization.

133120021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5787850.

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

The square root of 133120021 is about 11537.7649915397. The cubic root of 133120021 is about 510.6003707583.

Adding to 133120021 its reverse (120021331), we get a palindrome (253141352).

The spelling of 133120021 in words is "one hundred thirty-three million, one hundred twenty thousand, twenty-one".