133878881 has 4 divisors (see below), whose sum is σ = 133911492. Its totient is φ = 133846272.

The previous prime is 133878869. The next prime is 133878907. The reversal of 133878881 is 188878331.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 188878331 = 4591 ⋅41141.

It can be written as a sum of positive squares in 2 ways, for example, as 7203856 + 126675025 = 2684^2 + 11255^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-133878881 is a prime.

It is a super-2 number, since 2×133878881² = 35847109555624322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (133878821) 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, 9080 + ... + 18713.

It is an arithmetic number, because the mean of its divisors is an integer number (33477873).

Almost surely, 2^133878881 is an apocalyptic number.

It is an amenable number.

133878881 is a deficient number, since it is larger than the sum of its proper divisors (32611).

133878881 is an equidigital number, since it uses as much as digits as its factorization.

133878881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32610.

The product of its digits is 258048, while the sum is 47.

The square root of 133878881 is about 11570.6041761007. The cubic root of 133878881 is about 511.5687706598.

The spelling of 133878881 in words is "one hundred thirty-three million, eight hundred seventy-eight thousand, eight hundred eighty-one".