814165140721 has 3 divisors (see below), whose sum is σ = 814166043033. Its totient is φ = 814164238410.

The previous prime is 814165140707. The next prime is 814165140791. The reversal of 814165140721 is 127041561418.

The square root of 814165140721 is 902311.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 814165140721 - 2²⁷ = 814030922993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (814165140791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 451156 + ... + 1353466.

It is an arithmetic number, because the mean of its divisors is an integer number (271388681011).

Almost surely, 2^814165140721 is an apocalyptic number.

814165140721 is the 902311-st square number.

814165140721 is the 451156-th centered octagonal number.

It is an amenable number.

814165140721 is a deficient number, since it is larger than the sum of its proper divisors (902312).

814165140721 is an frugal number, since it uses more digits than its factorization.

814165140721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1804622 (or 902311 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 40.

The spelling of 814165140721 in words is "eight hundred fourteen billion, one hundred sixty-five million, one hundred forty thousand, seven hundred twenty-one".