133805645 has 4 divisors (see below), whose sum is σ = 160566780. Its totient is φ = 107044512.

The previous prime is 133805621. The next prime is 133805647. The reversal of 133805645 is 546508331.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 546508331 = 31 ⋅17629301.

It can be written as a sum of positive squares in 2 ways, for example, as 62267881 + 71537764 = 7891^2 + 8458^2 .

It is a cyclic number.

It is not a de Polignac number, because 133805645 - 2¹⁰ = 133804621 is a prime.

It is a super-3 number, since 3×133805645³ (a number of 25 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133805647) 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, 13380560 + ... + 13380569.

It is an arithmetic number, because the mean of its divisors is an integer number (40141695).

Almost surely, 2^133805645 is an apocalyptic number.

It is an amenable number.

133805645 is a deficient number, since it is larger than the sum of its proper divisors (26761135).

133805645 is an equidigital number, since it uses as much as digits as its factorization.

133805645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26761134.

The product of its (nonzero) digits is 43200, while the sum is 35.

The square root of 133805645 is about 11567.4389991908. The cubic root of 133805645 is about 511.4754721902.

The spelling of 133805645 in words is "one hundred thirty-three million, eight hundred five thousand, six hundred forty-five".