133446781 has 16 divisors (see below), whose sum is σ = 146608000. Its totient is φ = 120719808.

The previous prime is 133446779. The next prime is 133446791. The reversal of 133446781 is 187644331.

It is a cyclic number.

It is not a de Polignac number, because 133446781 - 2¹ = 133446779 is a prime.

It is a super-2 number, since 2×133446781² = 35616086718523922, 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 133446781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133446751) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 303760 + ... + 304198.

It is an arithmetic number, because the mean of its divisors is an integer number (9163000).

Almost surely, 2^133446781 is an apocalyptic number.

It is an amenable number.

133446781 is a deficient number, since it is larger than the sum of its proper divisors (13161219).

133446781 is a wasteful number, since it uses less digits than its factorization.

133446781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 868.

The product of its digits is 48384, while the sum is 37.

The square root of 133446781 is about 11551.9167673594. The cubic root of 133446781 is about 511.0178072157.

The spelling of 133446781 in words is "one hundred thirty-three million, four hundred forty-six thousand, seven hundred eighty-one".