654997221 has 12 divisors (see below), whose sum is σ = 955475820. Its totient is φ = 432340800.

The previous prime is 654997201. The next prime is 654997229. The reversal of 654997221 is 122799456.

It can be written as a sum of positive squares in 2 ways, for example, as 461648196 + 193349025 = 21486^2 + 13905^2 .

It is not a de Polignac number, because 654997221 - 2⁷ = 654997093 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (654997229) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 359376 + ... + 361193.

It is an arithmetic number, because the mean of its divisors is an integer number (79622985).

Almost surely, 2^654997221 is an apocalyptic number.

It is an amenable number.

654997221 is a deficient number, since it is larger than the sum of its proper divisors (300478599).

654997221 is a wasteful number, since it uses less digits than its factorization.

654997221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 720676 (or 720673 counting only the distinct ones).

The product of its digits is 272160, while the sum is 45.

The square root of 654997221 is about 25592.9134918243. The cubic root of 654997221 is about 868.4533320587.

The spelling of 654997221 in words is "six hundred fifty-four million, nine hundred ninety-seven thousand, two hundred twenty-one".