636794673540 has 192 divisors, whose sum is σ = 1825083187200. Its totient is φ = 165847661056.

The previous prime is 636794673503. The next prime is 636794673569. The reversal of 636794673540 is 45376497636.

It is a happy number.

It is a super-2 number, since 2×636794673540² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (60).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 628622074 + ... + 628623086.

It is an arithmetic number, because the mean of its divisors is an integer number (9505641600).

Almost surely, 2^636794673540 is an apocalyptic number.

636794673540 is a gapful number since it is divisible by the number (60) 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 636794673540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (912541593600).

636794673540 is an abundant number, since it is smaller than the sum of its proper divisors (1188288513660).

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

636794673540 is a wasteful number, since it uses less digits than its factorization.

636794673540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2066 (or 2064 counting only the distinct ones).

The product of its (nonzero) digits is 68584320, while the sum is 60.

The spelling of 636794673540 in words is "six hundred thirty-six billion, seven hundred ninety-four million, six hundred seventy-three thousand, five hundred forty".