20156222666 has 8 divisors (see below), whose sum is σ = 30511713540. Its totient is φ = 9985651488.

The previous prime is 20156222633. The next prime is 20156222689. The reversal of 20156222666 is 66622265102.

It can be written as a sum of positive squares in 2 ways, for example, as 20028193441 + 128029225 = 141521^2 + 11315^2 .

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

It is a super-2 number, since 2×20156222666² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46229651 + ... + 46230086.

Almost surely, 2^20156222666 is an apocalyptic number.

20156222666 is a deficient number, since it is larger than the sum of its proper divisors (10355490874).

20156222666 is a wasteful number, since it uses less digits than its factorization.

20156222666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92459848.

The product of its (nonzero) digits is 103680, while the sum is 38.

Adding to 20156222666 its reverse (66622265102), we get a palindrome (86778487768).

The spelling of 20156222666 in words is "twenty billion, one hundred fifty-six million, two hundred twenty-two thousand, six hundred sixty-six".