133979781 has 8 divisors (see below), whose sum is σ = 192381280. Its totient is φ = 82449072.

The previous prime is 133979777. The next prime is 133979809. The reversal of 133979781 is 187979331.

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

It is not a de Polignac number, because 133979781 - 2² = 133979777 is a prime.

It is a super-2 number, since 2×133979781² = 35901163433615922, which contains 22 as substring.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 133979781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133979711) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1717651 + ... + 1717728.

It is an arithmetic number, because the mean of its divisors is an integer number (24047660).

Almost surely, 2^133979781 is an apocalyptic number.

It is an amenable number.

133979781 is a deficient number, since it is larger than the sum of its proper divisors (58401499).

133979781 is a wasteful number, since it uses less digits than its factorization.

133979781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3435395.

The product of its digits is 285768, while the sum is 48.

The square root of 133979781 is about 11574.9635420592. The cubic root of 133979781 is about 511.6972557667.

The spelling of 133979781 in words is "one hundred thirty-three million, nine hundred seventy-nine thousand, seven hundred eighty-one".