20342777878878 has 144 divisors (see below), whose sum is σ = 51188929018416. Its totient is φ = 5342047441920.

The previous prime is 20342777878873. The next prime is 20342777878931. The reversal of 20342777878878 is 87887877724302.

It is a super-2 number, since 2×20342777878878² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (78).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20342777878873) by changing a digit.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 207443538 + ... + 207541578.

It is an arithmetic number, because the mean of its divisors is an integer number (355478673739).

Almost surely, 2^{20342777878878} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20342777878878, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25594464509208).

20342777878878 is an abundant number, since it is smaller than the sum of its proper divisors (30846151139538).

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

20342777878878 is a wasteful number, since it uses less digits than its factorization.

20342777878878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98539 (or 98299 counting only the distinct ones).

The product of its (nonzero) digits is 3304390656, while the sum is 78.

The spelling of 20342777878878 in words is "twenty trillion, three hundred forty-two billion, seven hundred seventy-seven million, eight hundred seventy-eight thousand, eight hundred seventy-eight".