654256117321 has 9 divisors (see below), whose sum is σ = 656047777581. Its totient is φ = 652469343372.

The previous prime is 654256117313. The next prime is 654256117343. The reversal of 654256117321 is 123711652456.

The square root of 654256117321 is 808861.

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

It is not a de Polignac number, because 654256117321 - 2³ = 654256117313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (654256117421) 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, 374501770 + ... + 374503516.

It is an arithmetic number, because the mean of its divisors is an integer number (72894197509).

Almost surely, 2^654256117321 is an apocalyptic number.

654256117321 is the 808861-st square number.

654256117321 is the 404431-st centered octagonal number.

It is an amenable number.

654256117321 is a deficient number, since it is larger than the sum of its proper divisors (1791660260).

654256117321 is an frugal number, since it uses more digits than its factorization.

654256117321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4420 (or 2210 counting only the distinct ones).

The product of its digits is 302400, while the sum is 43.

Adding to 654256117321 its reverse (123711652456), we get a palindrome (777967769777).

The spelling of 654256117321 in words is "six hundred fifty-four billion, two hundred fifty-six million, one hundred seventeen thousand, three hundred twenty-one".