133423644 has 48 divisors (see below), whose sum is σ = 326430720. Its totient is φ = 42335040.

The previous prime is 133423639. The next prime is 133423649. The reversal of 133423644 is 446324331.

It is an interprime number because it is at equal distance from previous prime (133423639) and next prime (133423649).

It is a Smith number, since the sum of its digits (30) coincides with the sum of the digits of its prime factors.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133423649) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62149 + ... + 64259.

It is an arithmetic number, because the mean of its divisors is an integer number (6800640).

Almost surely, 2^133423644 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 133423644, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (163215360).

133423644 is an abundant number, since it is smaller than the sum of its proper divisors (193007076).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

133423644 is a wasteful number, since it uses less digits than its factorization.

133423644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2370 (or 2368 counting only the distinct ones).

The product of its digits is 20736, while the sum is 30.

The square root of 133423644 is about 11550.9152884090. The cubic root of 133423644 is about 510.9882720899.

Adding to 133423644 its reverse (446324331), we get a palindrome (579747975).

The spelling of 133423644 in words is "one hundred thirty-three million, four hundred twenty-three thousand, six hundred forty-four".