133821979 has 16 divisors (see below), whose sum is σ = 142884000. Its totient is φ = 125122816.

The previous prime is 133821967. The next prime is 133822021. The reversal of 133821979 is 979128331.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-133821979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (133821929) 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 15 ways as a sum of consecutive naturals, for example, 127047 + ... + 128095.

It is an arithmetic number, because the mean of its divisors is an integer number (8930250).

Almost surely, 2^133821979 is an apocalyptic number.

133821979 is a deficient number, since it is larger than the sum of its proper divisors (9062021).

133821979 is a wasteful number, since it uses less digits than its factorization.

133821979 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1214.

The product of its digits is 81648, while the sum is 43.

The square root of 133821979 is about 11568.1450111935. The cubic root of 133821979 is about 511.4962837199.

The spelling of 133821979 in words is "one hundred thirty-three million, eight hundred twenty-one thousand, nine hundred seventy-nine".