242215531 has 2 divisors, whose sum is σ = 242215532. Its totient is φ = 242215530.

The previous prime is 242215513. The next prime is 242215559. The reversal of 242215531 is 135512242.

Together with previous prime (242215513) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 242215531 - 2⁷ = 242215403 is a prime.

It is a super-2 number, since 2×242215531² = 117336726915223922, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 242215496 and 242215505.

It is not a weakly prime, because it can be changed into another prime (242215931) 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 as a sum of consecutive naturals, namely, 121107765 + 121107766.

It is an arithmetic number, because the mean of its divisors is an integer number (121107766).

Almost surely, 2^242215531 is an apocalyptic number.

242215531 is a deficient number, since it is larger than the sum of its proper divisors (1).

242215531 is an equidigital number, since it uses as much as digits as its factorization.

242215531 is an odious number, because the sum of its binary digits is odd.

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

The square root of 242215531 is about 15563.2750730687. The cubic root of 242215531 is about 623.3529163175.

Adding to 242215531 its reverse (135512242), we get a palindrome (377727773).

The spelling of 242215531 in words is "two hundred forty-two million, two hundred fifteen thousand, five hundred thirty-one".