20345131615566 has 8 divisors (see below), whose sum is σ = 40690263231144. Its totient is φ = 6781710538520.

The previous prime is 20345131615559. The next prime is 20345131615619. The reversal of 20345131615566 is 66551613154302.

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

20345131615566 is an admirable number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1695427634625 + ... + 1695427634636.

It is an arithmetic number, because the mean of its divisors is an integer number (5086282903893).

Almost surely, 2^{20345131615566} is an apocalyptic number.

20345131615566 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

20345131615566 is a wasteful number, since it uses less digits than its factorization.

20345131615566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3390855269266.

The product of its (nonzero) digits is 1944000, while the sum is 48.

Adding to 20345131615566 its reverse (66551613154302), we get a palindrome (86896744769868).

The spelling of 20345131615566 in words is "twenty trillion, three hundred forty-five billion, one hundred thirty-one million, six hundred fifteen thousand, five hundred sixty-six".