5049665721 has 9 divisors (see below), whose sum is σ = 7294269541. Its totient is φ = 3366301692.

The previous prime is 5049665711. The next prime is 5049665723. The reversal of 5049665721 is 1275669405.

The square root of 5049665721 is 71061.

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

5049665721 is a `hidden beast` number, since 504 + 96 + 6 + 57 + 2 + 1 = 666.

It is a tau number, because it is divible by the number of its divisors (9).

It is not a de Polignac number, because 5049665721 - 2¹¹ = 5049663673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (5049665723) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 201340 + ... + 225026.

Almost surely, 2^5049665721 is an apocalyptic number.

5049665721 is the 71061-st square number.

5049665721 is the 35531-st centered octagonal number.

It is an amenable number.

5049665721 is a deficient number, since it is larger than the sum of its proper divisors (2244603820).

5049665721 is an frugal number, since it uses more digits than its factorization.

5049665721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47380 (or 23690 counting only the distinct ones).

The product of its (nonzero) digits is 453600, while the sum is 45.

The cubic root of 5049665721 is about 1715.6191154665.

The spelling of 5049665721 in words is "five billion, forty-nine million, six hundred sixty-five thousand, seven hundred twenty-one".