1381311816 has 128 divisors (see below), whose sum is σ = 3622268160. Its totient is φ = 438681600.

The previous prime is 1381311803. The next prime is 1381311821. The reversal of 1381311816 is 6181131831.

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10082500 + ... + 10082636.

It is an arithmetic number, because the mean of its divisors is an integer number (28298970).

Almost surely, 2^1381311816 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1381311816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1811134080).

1381311816 is an abundant number, since it is smaller than the sum of its proper divisors (2240956344).

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

1381311816 is a wasteful number, since it uses less digits than its factorization.

1381311816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 375 (or 371 counting only the distinct ones).

The product of its digits is 3456, while the sum is 33.

The square root of 1381311816 is about 37166.0034978204. The cubic root of 1381311816 is about 1113.6889457274.

The spelling of 1381311816 in words is "one billion, three hundred eighty-one million, three hundred eleven thousand, eight hundred sixteen".