66642152064 has 128 divisors (see below), whose sum is σ = 187711318080. Its totient is φ = 20876083200.

The previous prime is 66642151967. The next prime is 66642152069. The reversal of 66642152064 is 46025124666.

It is a tau number, because it is divible by the number of its divisors (128).

It is not an unprimeable number, because it can be changed into a prime (66642152069) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4568847 + ... + 4583409.

Almost surely, 2^66642152064 is an apocalyptic number.

66642152064 is a gapful number since it is divisible by the number (64) 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 66642152064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (93855659040).

66642152064 is an abundant number, since it is smaller than the sum of its proper divisors (121069166016).

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

66642152064 is a wasteful number, since it uses less digits than its factorization.

66642152064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15298 (or 15286 counting only the distinct ones).

The product of its (nonzero) digits is 414720, while the sum is 42.

The spelling of 66642152064 in words is "sixty-six billion, six hundred forty-two million, one hundred fifty-two thousand, sixty-four".