66406251250 has 20 divisors (see below), whose sum is σ = 124471879686. Its totient is φ = 26562500000.

The previous prime is 66406251229. The next prime is 66406251259. The reversal of 66406251250 is 5215260466.

It can be written as a sum of positive squares in 5 ways, for example, as 170537481 + 66235713769 = 13059^2 + 257363^2 .

It is not an unprimeable number, because it can be changed into a prime (66406251259) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 26561251 + ... + 26563750.

Almost surely, 2^66406251250 is an apocalyptic number.

66406251250 is a deficient number, since it is larger than the sum of its proper divisors (58065628436).

66406251250 is an equidigital number, since it uses as much as digits as its factorization.

66406251250 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53125023 (or 53125008 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 37.

The spelling of 66406251250 in words is "sixty-six billion, four hundred six million, two hundred fifty-one thousand, two hundred fifty".