66203381851 has 4 divisors (see below), whose sum is σ = 66647700000. Its totient is φ = 65759063704.

The previous prime is 66203381831. The next prime is 66203381857. The reversal of 66203381851 is 15818330266.

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

It is a cyclic number.

It is not a de Polignac number, because 66203381851 - 2²⁵ = 66169827419 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 66203381798 and 66203381807.

It is not an unprimeable number, because it can be changed into a prime (66203381857) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 222158851 + ... + 222159148.

It is an arithmetic number, because the mean of its divisors is an integer number (16661925000).

Almost surely, 2^66203381851 is an apocalyptic number.

66203381851 is a deficient number, since it is larger than the sum of its proper divisors (444318149).

66203381851 is a wasteful number, since it uses less digits than its factorization.

66203381851 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 444318148.

The product of its (nonzero) digits is 207360, while the sum is 43.

The spelling of 66203381851 in words is "sixty-six billion, two hundred three million, three hundred eighty-one thousand, eight hundred fifty-one".