1393171812 has 90 divisors (see below), whose sum is σ = 3688012482. Its totient is φ = 458597376.

The previous prime is 1393171771. The next prime is 1393171823. The reversal of 1393171812 is 2181713931.

It can be written as a sum of positive squares in 3 ways, for example, as 375816996 + 1017354816 = 19386^2 + 31896^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 3048288 + ... + 3048744.

Almost surely, 2^1393171812 is an apocalyptic number.

1393171812 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1393171812, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1844006241).

1393171812 is an abundant number, since it is smaller than the sum of its proper divisors (2294840670).

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

1393171812 is an equidigital number, since it uses as much as digits as its factorization.

1393171812 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 667 (or 559 counting only the distinct ones).

The product of its digits is 9072, while the sum is 36.

The square root of 1393171812 is about 37325.2168379502. The cubic root of 1393171812 is about 1116.8672585761.

The spelling of 1393171812 in words is "one billion, three hundred ninety-three million, one hundred seventy-one thousand, eight hundred twelve".