20345637666 has 64 divisors (see below), whose sum is σ = 43020149760. Its totient is φ = 6402073920.

The previous prime is 20345637647. The next prime is 20345637671. The reversal of 20345637666 is 66673654302.

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 31 ways as a sum of consecutive naturals, for example, 3315421 + ... + 3321551.

It is an arithmetic number, because the mean of its divisors is an integer number (672189840).

Almost surely, 2^20345637666 is an apocalyptic number.

20345637666 is an abundant number, since it is smaller than the sum of its proper divisors (22674512094).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20345637666 is a wasteful number, since it uses less digits than its factorization.

20345637666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6471.

The product of its (nonzero) digits is 3265920, while the sum is 48.

The spelling of 20345637666 in words is "twenty billion, three hundred forty-five million, six hundred thirty-seven thousand, six hundred sixty-six".