133206640 has 80 divisors (see below), whose sum is σ = 358548480. Its totient is φ = 45077760.

The previous prime is 133206637. The next prime is 133206673. The reversal of 133206640 is 46602331.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 42735 + ... + 45745.

It is an arithmetic number, because the mean of its divisors is an integer number (4481856).

Almost surely, 2^133206640 is an apocalyptic number.

133206640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 133206640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (179274240).

133206640 is an abundant number, since it is smaller than the sum of its proper divisors (225341840).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

133206640 is a wasteful number, since it uses less digits than its factorization.

133206640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3110 (or 3104 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 25.

The square root of 133206640 is about 11541.5180977201. The cubic root of 133206640 is about 510.7110931573.

Adding to 133206640 its reverse (46602331), we get a palindrome (179808971).

The spelling of 133206640 in words is "one hundred thirty-three million, two hundred six thousand, six hundred forty".