65815638736 has 80 divisors (see below), whose sum is σ = 133641446400. Its totient is φ = 31359910400.

The previous prime is 65815638727. The next prime is 65815638761. The reversal of 65815638736 is 63783651856.

It is a Harshad number since it is a multiple of its sum of digits (58).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11606910 + ... + 11612578.

It is an arithmetic number, because the mean of its divisors is an integer number (1670518080).

Almost surely, 2^65815638736 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 65815638736, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (66820723200).

65815638736 is an abundant number, since it is smaller than the sum of its proper divisors (67825807664).

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

65815638736 is a wasteful number, since it uses less digits than its factorization.

65815638736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6028 (or 6022 counting only the distinct ones).

The product of its digits is 21772800, while the sum is 58.

The spelling of 65815638736 in words is "sixty-five billion, eight hundred fifteen million, six hundred thirty-eight thousand, seven hundred thirty-six".