135280736640 has 384 divisors, whose sum is σ = 544779144000. Its totient is φ = 30920859648.

The previous prime is 135280736627. The next prime is 135280736641. The reversal of 135280736640 is 46637082531.

135280736640 is a `hidden beast` number, since 1 + 3 + 5 + 280 + 7 + 366 + 4 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (384).

It is a super-2 number, since 2×135280736640² (a number of 23 digits) contains 22 as substring.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135280736641) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1941444 + ... + 2009916.

Almost surely, 2^135280736640 is an apocalyptic number.

135280736640 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 135280736640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (272389572000).

135280736640 is an abundant number, since it is smaller than the sum of its proper divisors (409498407360).

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

135280736640 is an equidigital number, since it uses as much as digits as its factorization.

135280736640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68519 (or 68490 counting only the distinct ones).

The product of its (nonzero) digits is 725760, while the sum is 45.

The spelling of 135280736640 in words is "one hundred thirty-five billion, two hundred eighty million, seven hundred thirty-six thousand, six hundred forty".