66519710938 has 8 divisors (see below), whose sum is σ = 99942340788. Its totient is φ = 33205597344.

The previous prime is 66519710897. The next prime is 66519710993. The reversal of 66519710938 is 83901791566.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 38340381249 + 28179329689 = 195807^2 + 167867^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-3 number, since 3×66519710938³ (a number of 33 digits) contains 333 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27127531 + ... + 27129982.

Almost surely, 2^66519710938 is an apocalyptic number.

66519710938 is a deficient number, since it is larger than the sum of its proper divisors (33422629850).

66519710938 is a wasteful number, since it uses less digits than its factorization.

66519710938 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54258128.

The product of its (nonzero) digits is 2449440, while the sum is 55.

The spelling of 66519710938 in words is "sixty-six billion, five hundred nineteen million, seven hundred ten thousand, nine hundred thirty-eight".