1821311713 has 8 divisors (see below), whose sum is σ = 1962307368. Its totient is φ = 1680443904.

The previous prime is 1821311707. The next prime is 1821311729. The reversal of 1821311713 is 3171131281.

It can be written as a sum of positive squares in 4 ways, for example, as 106357969 + 1714953744 = 10313^2 + 41412^2 .

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 1821311713 - 2²¹ = 1819214561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1821311773) 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, 1270 + ... + 60367.

It is an arithmetic number, because the mean of its divisors is an integer number (245288421).

Almost surely, 2^1821311713 is an apocalyptic number.

1821311713 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1821311713 is a deficient number, since it is larger than the sum of its proper divisors (140995655).

1821311713 is a wasteful number, since it uses less digits than its factorization.

1821311713 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63923.

The product of its digits is 1008, while the sum is 28.

The square root of 1821311713 is about 42676.8287598786. The cubic root of 1821311713 is about 1221.2223959088. Note that the first 3 decimals are identical.

Adding to 1821311713 its reverse (3171131281), we get a palindrome (4992442994).

The spelling of 1821311713 in words is "one billion, eight hundred twenty-one million, three hundred eleven thousand, seven hundred thirteen".