1278422838 has 180 divisors, whose sum is σ = 3665534796. Its totient is φ = 332057880.

The previous prime is 1278422837. The next prime is 1278422851. The reversal of 1278422838 is 8382248721.

It is a junction number, because it is equal to n+sod(n) for n = 1278422793 and 1278422802.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1278422837) by changing a digit.

It is a polite number, since it can be written in 89 ways as a sum of consecutive naturals, for example, 116220253 + ... + 116220263.

Almost surely, 2^1278422838 is an apocalyptic number.

1278422838 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1278422838, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1832767398).

1278422838 is an abundant number, since it is smaller than the sum of its proper divisors (2387111958).

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

1278422838 is an frugal number, since it uses more digits than its factorization.

1278422838 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83 (or 23 counting only the distinct ones).

The product of its digits is 344064, while the sum is 45.

The square root of 1278422838 is about 35755.0393371340. The cubic root of 1278422838 is about 1085.3209179044.

The spelling of 1278422838 in words is "one billion, two hundred seventy-eight million, four hundred twenty-two thousand, eight hundred thirty-eight".