133621161 has 4 divisors (see below), whose sum is σ = 178161552. Its totient is φ = 89080772.

The previous prime is 133621151. The next prime is 133621193. The reversal of 133621161 is 161126331.

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: 161126331 = 3 ⋅53708777.

It is a cyclic number.

It is not a de Polignac number, because 133621161 - 2⁹ = 133620649 is a prime.

It is a super-2 number, since 2×133621161² = 35709229333975842, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (133621121) 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, 22270191 + ... + 22270196.

It is an arithmetic number, because the mean of its divisors is an integer number (44540388).

Almost surely, 2^133621161 is an apocalyptic number.

It is an amenable number.

133621161 is a deficient number, since it is larger than the sum of its proper divisors (44540391).

133621161 is an equidigital number, since it uses as much as digits as its factorization.

133621161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44540390.

The product of its digits is 648, while the sum is 24.

The square root of 133621161 is about 11559.4619684482. The cubic root of 133621161 is about 511.2402991526.

Adding to 133621161 its reverse (161126331), we get a palindrome (294747492).

The spelling of 133621161 in words is "one hundred thirty-three million, six hundred twenty-one thousand, one hundred sixty-one".