133685640 has 320 divisors, whose sum is σ = 510174720. Its totient is φ = 31363200.

The previous prime is 133685633. The next prime is 133685677. The reversal of 133685640 is 46586331.

133685640 is a `hidden beast` number, since 1 + 3 + 3 + 6 + 8 + 5 + 640 = 666.

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 = 133685595 and 133685604.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 4312425 + ... + 4312455.

It is an arithmetic number, because the mean of its divisors is an integer number (1594296).

Almost surely, 2^133685640 is an apocalyptic number.

133685640 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 133685640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (255087360).

133685640 is an abundant number, since it is smaller than the sum of its proper divisors (376489080).

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

133685640 is a wasteful number, since it uses less digits than its factorization.

133685640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87 (or 52 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The square root of 133685640 is about 11562.2506459599. The cubic root of 133685640 is about 511.3225190697.

The spelling of 133685640 in words is "one hundred thirty-three million, six hundred eighty-five thousand, six hundred forty".