5243513217721 has 4 divisors (see below), whose sum is σ = 5246170854372. Its totient is φ = 5240855581072.

The previous prime is 5243513217601. The next prime is 5243513217737. The reversal of 5243513217721 is 1277123153425.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3084024187321 + 2159489030400 = 1756139^2 + 1469520^2 .

It is a cyclic number.

It is not a de Polignac number, because 5243513217721 - 2³⁹ = 4693757403833 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (5243513214721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1328815366 + ... + 1328819311.

It is an arithmetic number, because the mean of its divisors is an integer number (1311542713593).

Almost surely, 2^{5243513217721} is an apocalyptic number.

It is an amenable number.

5243513217721 is a deficient number, since it is larger than the sum of its proper divisors (2657636651).

5243513217721 is a wasteful number, since it uses less digits than its factorization.

5243513217721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2657636650.

The product of its digits is 352800, while the sum is 43.

The spelling of 5243513217721 in words is "five trillion, two hundred forty-three billion, five hundred thirteen million, two hundred seventeen thousand, seven hundred twenty-one".