133538881 has 8 divisors (see below), whose sum is σ = 157878720. Its totient is φ = 110514768.

The previous prime is 133538869. The next prime is 133538921. The reversal of 133538881 is 188835331.

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

It is not a de Polignac number, because 133538881 - 2⁷ = 133538753 is a prime.

It is a super-2 number, since 2×133538881² = 35665265477464322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (133538861) 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, 328711 + ... + 329116.

It is an arithmetic number, because the mean of its divisors is an integer number (19734840).

Almost surely, 2^133538881 is an apocalyptic number.

It is an amenable number.

133538881 is a deficient number, since it is larger than the sum of its proper divisors (24339839).

133538881 is an equidigital number, since it uses as much as digits as its factorization.

133538881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 657863.

The product of its digits is 69120, while the sum is 40.

The square root of 133538881 is about 11555.9024312254. The cubic root of 133538881 is about 511.1353420022.

The spelling of 133538881 in words is "one hundred thirty-three million, five hundred thirty-eight thousand, eight hundred eighty-one".