133287840 has 216 divisors, whose sum is σ = 529385220. Its totient is φ = 30449664.

The previous prime is 133287839. The next prime is 133287841. The reversal of 133287840 is 48782331.

It is an interprime number because it is at equal distance from previous prime (133287839) and next prime (133287841).

It can be written as a sum of positive squares in 2 ways, for example, as 132434064 + 853776 = 11508^2 + 924^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 133287795 and 133287804.

It is not an unprimeable number, because it can be changed into a prime (133287841) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 69616 + ... + 71504.

Almost surely, 2^133287840 is an apocalyptic number.

133287840 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 133287840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (264692610).

133287840 is an abundant number, since it is smaller than the sum of its proper divisors (396097380).

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

133287840 is a wasteful number, since it uses less digits than its factorization.

133287840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1924 (or 1906 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 36.

The square root of 133287840 is about 11545.0352966113. The cubic root of 133287840 is about 510.8148450354.

The spelling of 133287840 in words is "one hundred thirty-three million, two hundred eighty-seven thousand, eight hundred forty".