66401559226 has 8 divisors (see below), whose sum is σ = 99942279444. Its totient is φ = 33087466080.

The previous prime is 66401559181. The next prime is 66401559247. The reversal of 66401559226 is 62295510466.

It is a Cunningham number, because it is equal to 257685²+1.

It can be written as a sum of positive squares in 2 ways, for example, as 66401559225 + 1 = 257685^2 + 1^2 .

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 56656035 + ... + 56657206.

Almost surely, 2^66401559226 is an apocalyptic number.

66401559226 is a deficient number, since it is larger than the sum of its proper divisors (33540720218).

66401559226 is a wasteful number, since it uses less digits than its factorization.

66401559226 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 113313536.

The product of its (nonzero) digits is 777600, while the sum is 46.

The spelling of 66401559226 in words is "sixty-six billion, four hundred one million, five hundred fifty-nine thousand, two hundred twenty-six".