2778338919781 has 8 divisors (see below), whose sum is σ = 2925163138400. Its totient is φ = 2631574286640.

The previous prime is 2778338919749. The next prime is 2778338919799. The reversal of 2778338919781 is 1879198338772.

2778338919781 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 2778338919781 - 2⁵ = 2778338919749 is a prime.

It is a super-2 number, since 2×2778338919781² (a number of 26 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2778338919581) 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, 14800635 + ... + 14987176.

It is an arithmetic number, because the mean of its divisors is an integer number (365645392300).

Almost surely, 2^{2778338919781} is an apocalyptic number.

It is an amenable number.

2778338919781 is a deficient number, since it is larger than the sum of its proper divisors (146824218619).

2778338919781 is a wasteful number, since it uses less digits than its factorization.

2778338919781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29792739.

The product of its digits is 256048128, while the sum is 73.

The spelling of 2778338919781 in words is "two trillion, seven hundred seventy-eight billion, three hundred thirty-eight million, nine hundred nineteen thousand, seven hundred eighty-one".