133055561 has 8 divisors (see below), whose sum is σ = 135574560. Its totient is φ = 130545472.

The previous prime is 133055519. The next prime is 133055581. The reversal of 133055561 is 165550331.

133055561 = 428² + 429² + ... + 781².

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 133055561 - 2⁶ = 133055497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (133055581) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 33086 + ... + 36888.

It is an arithmetic number, because the mean of its divisors is an integer number (16946820).

Almost surely, 2^133055561 is an apocalyptic number.

It is an amenable number.

133055561 is a deficient number, since it is larger than the sum of its proper divisors (2518999).

133055561 is an equidigital number, since it uses as much as digits as its factorization.

133055561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4455.

The product of its (nonzero) digits is 6750, while the sum is 29.

The square root of 133055561 is about 11534.9712179962. The cubic root of 133055561 is about 510.5179423513.

The spelling of 133055561 in words is "one hundred thirty-three million, fifty-five thousand, five hundred sixty-one".