66403703840 has 48 divisors (see below), whose sum is σ = 156914088408. Its totient is φ = 26555498496.

The previous prime is 66403703831. The next prime is 66403703843. The reversal of 66403703840 is 4830730466.

66403703840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 63542309776 + 2861394064 = 252076^2 + 53492^2 .

It is not an unprimeable number, because it can be changed into a prime (66403703843) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 703274 + ... + 792086.

Almost surely, 2^66403703840 is an apocalyptic number.

It is an amenable number.

66403703840 is an abundant number, since it is smaller than the sum of its proper divisors (90510384568).

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

66403703840 is a wasteful number, since it uses less digits than its factorization.

66403703840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93501 (or 93493 counting only the distinct ones).

The product of its (nonzero) digits is 290304, while the sum is 41.

The spelling of 66403703840 in words is "sixty-six billion, four hundred three million, seven hundred three thousand, eight hundred forty".