20778283206457 has 8 divisors (see below), whose sum is σ = 25143468754176. Its totient is φ = 16762312502592.

The previous prime is 20778283206427. The next prime is 20778283206481. The reversal of 20778283206457 is 75460238287702.

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 20778283206457 - 2¹⁹ = 20778282682169 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20778283206395 and 20778283206404.

It is not an unprimeable number, because it can be changed into a prime (20778283206427) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 87303710833 + ... + 87303711070.

It is an arithmetic number, because the mean of its divisors is an integer number (3142933594272).

Almost surely, 2^{20778283206457} is an apocalyptic number.

It is an amenable number.

20778283206457 is a deficient number, since it is larger than the sum of its proper divisors (4365185547719).

20778283206457 is a wasteful number, since it uses less digits than its factorization.

20778283206457 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174607421927.

The product of its (nonzero) digits is 63221760, while the sum is 61.

The spelling of 20778283206457 in words is "twenty trillion, seven hundred seventy-eight billion, two hundred eighty-three million, two hundred six thousand, four hundred fifty-seven".