20778544587702 has 64 divisors (see below), whose sum is σ = 47335720978944. Its totient is φ = 6018994544640.

The previous prime is 20778544587673. The next prime is 20778544587709.

20778544587702 is nontrivially palindromic in base 10.

It is a Smith number, since the sum of its digits (66) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20778544587709) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1861323 + ... + 6709814.

It is an arithmetic number, because the mean of its divisors is an integer number (739620640296).

Almost surely, 2^{20778544587702} is an apocalyptic number.

20778544587702 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

20778544587702 is an abundant number, since it is smaller than the sum of its proper divisors (26557176391242).

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

20778544587702 is a wasteful number, since it uses less digits than its factorization.

20778544587702 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8572773.

The product of its (nonzero) digits is 245862400, while the sum is 66.

The spelling of 20778544587702 in words is "twenty trillion, seven hundred seventy-eight billion, five hundred forty-four million, five hundred eighty-seven thousand, seven hundred two".