531542221 has 16 divisors (see below), whose sum is σ = 623462400. Its totient is φ = 443682288.

The previous prime is 531542191. The next prime is 531542239. The reversal of 531542221 is 122245135.

It is not a de Polignac number, because 531542221 - 2⁹ = 531541709 is a prime.

It is a super-2 number, since 2×531542221² = 565074265411225682, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (531542251) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 105600 + ... + 110518.

It is an arithmetic number, because the mean of its divisors is an integer number (38966400).

Almost surely, 2^531542221 is an apocalyptic number.

It is an amenable number.

531542221 is a deficient number, since it is larger than the sum of its proper divisors (91920179).

531542221 is a wasteful number, since it uses less digits than its factorization.

531542221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5328.

The product of its digits is 2400, while the sum is 25.

The square root of 531542221 is about 23055.1994352684. The cubic root of 531542221 is about 810.0514223311.

Adding to 531542221 its reverse (122245135), we get a palindrome (653787356).

The spelling of 531542221 in words is "five hundred thirty-one million, five hundred forty-two thousand, two hundred twenty-one".