2584663920721 has 9 divisors (see below), whose sum is σ = 2599970311729. Its totient is φ = 2569447144336.

The previous prime is 2584663920689. The next prime is 2584663920749. The reversal of 2584663920721 is 1270293664852.

It is a happy number.

The square root of 2584663920721 is 1607689.

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

It can be written as a sum of positive squares in 4 ways, for example, as 1700655121 + 2582963265600 = 41239^2 + 1607160^2 .

It is not a de Polignac number, because 2584663920721 - 2⁵ = 2584663920689 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2584663920521) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 278125551 + ... + 278134843.

It is a 1-persistent number, because it is pandigital, but 2⋅2584663920721 = 5169327841442 is not.

Almost surely, 2^{2584663920721} is an apocalyptic number.

2584663920721 is the 1607689-th square number.

2584663920721 is the 803845-th centered octagonal number.

It is an amenable number.

2584663920721 is a deficient number, since it is larger than the sum of its proper divisors (15306391008).

2584663920721 is an frugal number, since it uses more digits than its factorization.

2584663920721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18932 (or 9466 counting only the distinct ones).

The product of its (nonzero) digits is 8709120, while the sum is 55.

The spelling of 2584663920721 in words is "two trillion, five hundred eighty-four billion, six hundred sixty-three million, nine hundred twenty thousand, seven hundred twenty-one".