133157781 has 12 divisors (see below), whose sum is σ = 192803520. Its totient is φ = 88557480.

The previous prime is 133157777. The next prime is 133157831. The reversal of 133157781 is 187751331.

It is a happy number.

133157781 is a `hidden beast` number, since 1 + 3 + 3 + 1 + 577 + 81 = 666.

It is not a de Polignac number, because 133157781 - 2² = 133157777 is a prime.

It is a super-2 number, since 2×133157781² = 35461989281687922, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133157711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13885 + ... + 21426.

It is an arithmetic number, because the mean of its divisors is an integer number (16066960).

Almost surely, 2^133157781 is an apocalyptic number.

It is an amenable number.

133157781 is a deficient number, since it is larger than the sum of its proper divisors (59645739).

133157781 is a wasteful number, since it uses less digits than its factorization.

133157781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35736 (or 35733 counting only the distinct ones).

The product of its digits is 17640, while the sum is 36.

The square root of 133157781 is about 11539.4012409657. The cubic root of 133157781 is about 510.6486441063.

The spelling of 133157781 in words is "one hundred thirty-three million, one hundred fifty-seven thousand, seven hundred eighty-one".