133171728 has 20 divisors (see below), whose sum is σ = 344027088. Its totient is φ = 44390560.

The previous prime is 133171697. The next prime is 133171729. The reversal of 133171728 is 827171331.

It is not an unprimeable number, because it can be changed into a prime (133171729) 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, 1387158 + ... + 1387253.

Almost surely, 2^133171728 is an apocalyptic number.

It is an amenable number.

133171728 is an abundant number, since it is smaller than the sum of its proper divisors (210855360).

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

133171728 is a wasteful number, since it uses less digits than its factorization.

133171728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2774422 (or 2774416 counting only the distinct ones).

The product of its digits is 7056, while the sum is 33.

The square root of 133171728 is about 11540.0055459259. The cubic root of 133171728 is about 510.6664719993. Note that the first 3 decimals are identical.

The spelling of 133171728 in words is "one hundred thirty-three million, one hundred seventy-one thousand, seven hundred twenty-eight".