66722978480 has 80 divisors (see below), whose sum is σ = 159589249920. Its totient is φ = 25930469376.

The previous prime is 66722978473. The next prime is 66722978521. The reversal of 66722978480 is 8487922766.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×66722978480² (a number of 22 digits) contains 22 as substring.

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, 450356 + ... + 579884.

It is an arithmetic number, because the mean of its divisors is an integer number (1994865624).

Almost surely, 2^66722978480 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 66722978480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (79794624960).

66722978480 is an abundant number, since it is smaller than the sum of its proper divisors (92866271440).

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

66722978480 is a wasteful number, since it uses less digits than its factorization.

66722978480 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129726 (or 129720 counting only the distinct ones).

The product of its (nonzero) digits is 16257024, while the sum is 59.

The spelling of 66722978480 in words is "sixty-six billion, seven hundred twenty-two million, nine hundred seventy-eight thousand, four hundred eighty".