654171998481 has 27 divisors (see below), whose sum is σ = 1003831250331. Its totient is φ = 410434979904.

The previous prime is 654171998479. The next prime is 654171998489. The reversal of 654171998481 is 184899171456.

The square root of 654171998481 is 808809.

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

654171998481 is a `hidden beast` number, since 6 + 54 + 1 + 7 + 19 + 98 + 481 = 666.

It can be written as a sum of positive squares in only one way, i.e., 509303459025 + 144868539456 = 713655^2 + 380616^2 .

It is not a de Polignac number, because 654171998481 - 2¹ = 654171998479 is a prime.

It is a super-2 number, since 2×654171998481² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (654171998489) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 41241330 + ... + 41257188.

Almost surely, 2^654171998481 is an apocalyptic number.

654171998481 is the 808809-th square number.

654171998481 is the 404405-th centered octagonal number.

It is an amenable number.

654171998481 is a deficient number, since it is larger than the sum of its proper divisors (349659251850).

654171998481 is an frugal number, since it uses more digits than its factorization.

654171998481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31758 (or 15879 counting only the distinct ones).

The product of its digits is 17418240, while the sum is 63.

The spelling of 654171998481 in words is "six hundred fifty-four billion, one hundred seventy-one million, nine hundred ninety-eight thousand, four hundred eighty-one".