133621 has 4 divisors (see below), whose sum is σ = 136512. Its totient is φ = 130732.

The previous prime is 133597. The next prime is 133631. The reversal of 133621 is 126331.

133621 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 133621 - 2⁷ = 133493 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 133595 and 133604.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133631) 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, 1375 + ... + 1468.

It is an arithmetic number, because the mean of its divisors is an integer number (34128).

2¹³³⁶²¹ is an apocalyptic number.

It is an amenable number.

133621 is a deficient number, since it is larger than the sum of its proper divisors (2891).

133621 is an equidigital number, since it uses as much as digits as its factorization.

133621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2890.

The product of its digits is 108, while the sum is 16.

The square root of 133621 is about 365.5420632431. The cubic root of 133621 is about 51.1240093822.

Adding to 133621 its reverse (126331), we get a palindrome (259952).

The spelling of 133621 in words is "one hundred thirty-three thousand, six hundred twenty-one".