21042240331 has 16 divisors (see below), whose sum is σ = 25610088384. Its totient is φ = 16877113344.

The previous prime is 21042240287. The next prime is 21042240341. The reversal of 21042240331 is 13304224012.

It is not a de Polignac number, because 21042240331 - 2⁷ = 21042240203 is a prime.

It is a super-2 number, since 2×21042240331² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21042240341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 490470 + ... + 531643.

It is an arithmetic number, because the mean of its divisors is an integer number (1600630524).

Almost surely, 2^21042240331 is an apocalyptic number.

21042240331 is a deficient number, since it is larger than the sum of its proper divisors (4567848053).

21042240331 is a wasteful number, since it uses less digits than its factorization.

21042240331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1022310.

The product of its (nonzero) digits is 1152, while the sum is 22.

Adding to 21042240331 its reverse (13304224012), we get a palindrome (34346464343).

The spelling of 21042240331 in words is "twenty-one billion, forty-two million, two hundred forty thousand, three hundred thirty-one".