133669728 has 36 divisors (see below), whose sum is σ = 380124108. Its totient is φ = 44556480.

The previous prime is 133669687. The next prime is 133669747. The reversal of 133669728 is 827966331.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 231778 + ... + 232353.

It is an arithmetic number, because the mean of its divisors is an integer number (10559003).

Almost surely, 2^133669728 is an apocalyptic number.

133669728 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is an amenable number.

133669728 is an abundant number, since it is smaller than the sum of its proper divisors (246454380).

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

133669728 is a wasteful number, since it uses less digits than its factorization.

133669728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 464147 (or 464136 counting only the distinct ones).

The product of its digits is 326592, while the sum is 45.

The square root of 133669728 is about 11561.5625241574. The cubic root of 133669728 is about 511.3022314588.

The spelling of 133669728 in words is "one hundred thirty-three million, six hundred sixty-nine thousand, seven hundred twenty-eight".