531221011 has 8 divisors (see below), whose sum is σ = 546022400. Its totient is φ = 516530952.

The previous prime is 531220993. The next prime is 531221017. The reversal of 531221011 is 110122135.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 531221011 - 2⁵ = 531220979 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (531221017) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18111 + ... + 37288.

It is an arithmetic number, because the mean of its divisors is an integer number (68252800).

Almost surely, 2^531221011 is an apocalyptic number.

531221011 is a deficient number, since it is larger than the sum of its proper divisors (14801389).

531221011 is a wasteful number, since it uses less digits than its factorization.

531221011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55665.

The product of its (nonzero) digits is 60, while the sum is 16.

The square root of 531221011 is about 23048.2322749490. The cubic root of 531221011 is about 809.8882185837. Note that the first 3 decimals are identical.

Adding to 531221011 its reverse (110122135), we get a palindrome (641343146).

The spelling of 531221011 in words is "five hundred thirty-one million, two hundred twenty-one thousand, eleven".