20780557718167 has 8 divisors (see below), whose sum is σ = 22379313754224. Its totient is φ = 19181837624448.

The previous prime is 20780557717967. The next prime is 20780557718177. The reversal of 20780557718167 is 76181775508702.

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

It is a cyclic number.

It is not a de Polignac number, because 20780557718167 - 2¹⁵ = 20780557685399 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20780557718099 and 20780557718108.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20780557718177) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 7778773 + ... + 10102990.

It is an arithmetic number, because the mean of its divisors is an integer number (2797414219278).

Almost surely, 2^{20780557718167} is an apocalyptic number.

20780557718167 is a deficient number, since it is larger than the sum of its proper divisors (1598756036057).

20780557718167 is a wasteful number, since it uses less digits than its factorization.

20780557718167 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17971169.

The product of its (nonzero) digits is 46099200, while the sum is 64.

The spelling of 20780557718167 in words is "twenty trillion, seven hundred eighty billion, five hundred fifty-seven million, seven hundred eighteen thousand, one hundred sixty-seven".