64036535640 has 256 divisors, whose sum is σ = 240476221440. Its totient is φ = 13252800000.

The previous prime is 64036535617. The next prime is 64036535659. The reversal of 64036535640 is 4653563046.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 64036535592 and 64036535601.

It is a congruent number.

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, 2305435 + ... + 2333045.

It is an arithmetic number, because the mean of its divisors is an integer number (939360240).

Almost surely, 2^64036535640 is an apocalyptic number.

64036535640 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 64036535640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (120238110720).

64036535640 is an abundant number, since it is smaller than the sum of its proper divisors (176439685800).

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

64036535640 is a wasteful number, since it uses less digits than its factorization.

64036535640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27894 (or 27890 counting only the distinct ones).

The product of its (nonzero) digits is 777600, while the sum is 42.

The spelling of 64036535640 in words is "sixty-four billion, thirty-six million, five hundred thirty-five thousand, six hundred forty".