66407138536 has 32 divisors (see below), whose sum is σ = 129315501000. Its totient is φ = 31943172096.

The previous prime is 66407138503. The next prime is 66407138569. The reversal of 66407138536 is 63583170466.

66407138536 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (66407138503) and next prime (66407138569).

It can be written as a sum of positive squares in 4 ways, for example, as 59267902500 + 7139236036 = 243450^2 + 84494^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 66407138536.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1234041 + ... + 1286728.

Almost surely, 2^66407138536 is an apocalyptic number.

It is an amenable number.

66407138536 is a deficient number, since it is larger than the sum of its proper divisors (62908362464).

66407138536 is a wasteful number, since it uses less digits than its factorization.

66407138536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2520901 (or 2520897 counting only the distinct ones).

The product of its (nonzero) digits is 2177280, while the sum is 49.

The spelling of 66407138536 in words is "sixty-six billion, four hundred seven million, one hundred thirty-eight thousand, five hundred thirty-six".