133149891 has 32 divisors (see below), whose sum is σ = 214466560. Its totient is φ = 71780256.

The previous prime is 133149859. The next prime is 133149893. The reversal of 133149891 is 198941331.

It is a happy number.

It is not a de Polignac number, because 133149891 - 2⁵ = 133149859 is a prime.

It is not an unprimeable number, because it can be changed into a prime (133149893) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 121950 + ... + 123036.

It is an arithmetic number, because the mean of its divisors is an integer number (6702080).

Almost surely, 2^133149891 is an apocalyptic number.

133149891 is a deficient number, since it is larger than the sum of its proper divisors (81316669).

133149891 is a wasteful number, since it uses less digits than its factorization.

133149891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1423.

The product of its digits is 23328, while the sum is 39.

The square root of 133149891 is about 11539.0593637436. The cubic root of 133149891 is about 510.6385580832.

The spelling of 133149891 in words is "one hundred thirty-three million, one hundred forty-nine thousand, eight hundred ninety-one".