242539987 has 2 divisors, whose sum is σ = 242539988. Its totient is φ = 242539986.

The previous prime is 242539981. The next prime is 242540009. The reversal of 242539987 is 789935242.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 242539987 - 2⁷ = 242539859 is a prime.

It is a super-3 number, since 3×242539987³ (a number of 26 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 242539987.

It is not a weakly prime, because it can be changed into another prime (242539981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121269993 + 121269994.

It is an arithmetic number, because the mean of its divisors is an integer number (121269994).

Almost surely, 2^242539987 is an apocalyptic number.

242539987 is a deficient number, since it is larger than the sum of its proper divisors (1).

242539987 is an equidigital number, since it uses as much as digits as its factorization.

242539987 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1088640, while the sum is 49.

The square root of 242539987 is about 15573.6953546678. The cubic root of 242539987 is about 623.6311263246.

The spelling of 242539987 in words is "two hundred forty-two million, five hundred thirty-nine thousand, nine hundred eighty-seven".