133326991 has 12 divisors (see below), whose sum is σ = 156055512. Its totient is φ = 113572368.

The previous prime is 133326989. The next prime is 133327037. The reversal of 133326991 is 199623331.

It is not a de Polignac number, because 133326991 - 2¹ = 133326989 is a prime.

It is a super-2 number, since 2×133326991² = 35552173058228162, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 133326991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133326931) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 360 + ... + 16333.

It is an arithmetic number, because the mean of its divisors is an integer number (13004626).

Almost surely, 2^133326991 is an apocalyptic number.

133326991 is a deficient number, since it is larger than the sum of its proper divisors (22728521).

133326991 is a wasteful number, since it uses less digits than its factorization.

133326991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16870 (or 16863 counting only the distinct ones).

The product of its digits is 26244, while the sum is 37.

The square root of 133326991 is about 11546.7307494373. The cubic root of 133326991 is about 510.8648544842.

The spelling of 133326991 in words is "one hundred thirty-three million, three hundred twenty-six thousand, nine hundred ninety-one".