19348464918721 has 3 divisors (see below), whose sum is σ = 19348469317411. Its totient is φ = 19348460520032.

The previous prime is 19348464918709. The next prime is 19348464918799. The reversal of 19348464918721 is 12781946484391.

The square root of 19348464918721 is 4398689.

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 can be written as a sum of positive squares in only one way, i.e., 7621127688321 + 11727337230400 = 2760639^2 + 3424520^2 .

It is not a de Polignac number, because 19348464918721 - 2²³ = 19348456530113 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19348464918221) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 2199345 + ... + 6598033.

Almost surely, 2^{19348464918721} is an apocalyptic number.

19348464918721 is the 4398689-th square number.

19348464918721 is the 2199345-th centered octagonal number.

It is an amenable number.

19348464918721 is a deficient number, since it is larger than the sum of its proper divisors (4398690).

19348464918721 is an frugal number, since it uses more digits than its factorization.

19348464918721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8797378 (or 4398689 counting only the distinct ones).

The product of its digits is 83607552, while the sum is 67.

The spelling of 19348464918721 in words is "nineteen trillion, three hundred forty-eight billion, four hundred sixty-four million, nine hundred eighteen thousand, seven hundred twenty-one".