66325136640 has 432 divisors, whose sum is σ = 247568560512. Its totient is φ = 14824194048.

The previous prime is 66325136629. The next prime is 66325136653. The reversal of 66325136640 is 4663152366.

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 = 66325136592 and 66325136601.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 59377362 + ... + 59378478.

Almost surely, 2^66325136640 is an apocalyptic number.

66325136640 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 66325136640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (123784280256).

66325136640 is an abundant number, since it is smaller than the sum of its proper divisors (181243423872).

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

66325136640 is a wasteful number, since it uses less digits than its factorization.

66325136640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1242 (or 1181 counting only the distinct ones).

The product of its (nonzero) digits is 466560, while the sum is 42.

The spelling of 66325136640 in words is "sixty-six billion, three hundred twenty-five million, one hundred thirty-six thousand, six hundred forty".