1389667892778 has 240 divisors, whose sum is σ = 3516132533760. Its totient is φ = 409722287040.

The previous prime is 1389667892759. The next prime is 1389667892803. The reversal of 1389667892778 is 8772987669831.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 1389667892697 and 1389667892706.

It is an unprimeable number.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 159379503 + ... + 159388221.

It is an arithmetic number, because the mean of its divisors is an integer number (14650552224).

Almost surely, 2^{1389667892778} is an apocalyptic number.

1389667892778 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 1389667892778, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1758066266880).

1389667892778 is an abundant number, since it is smaller than the sum of its proper divisors (2126464640982).

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

1389667892778 is a wasteful number, since it uses less digits than its factorization.

1389667892778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8975 (or 8955 counting only the distinct ones).

The product of its digits is 3072577536, while the sum is 81.

The spelling of 1389667892778 in words is "one trillion, three hundred eighty-nine billion, six hundred sixty-seven million, eight hundred ninety-two thousand, seven hundred seventy-eight".