66139950999 has 4 divisors (see below), whose sum is σ = 88186601336. Its totient is φ = 44093300664.

The previous prime is 66139950997. The next prime is 66139951027. The reversal of 66139950999 is 99905993166.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 66139950999 - 2¹ = 66139950997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66139950997) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11023325164 + ... + 11023325169.

It is an arithmetic number, because the mean of its divisors is an integer number (22046650334).

Almost surely, 2^66139950999 is an apocalyptic number.

66139950999 is a deficient number, since it is larger than the sum of its proper divisors (22046650337).

66139950999 is a wasteful number, since it uses less digits than its factorization.

66139950999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22046650336.

The product of its (nonzero) digits is 31886460, while the sum is 66.

The spelling of 66139950999 in words is "sixty-six billion, one hundred thirty-nine million, nine hundred fifty thousand, nine hundred ninety-nine".