242551 has 2 divisors, whose sum is σ = 242552. Its totient is φ = 242550.

The previous prime is 242533. The next prime is 242591. The reversal of 242551 is 155242.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 242551 - 2⁵ = 242519 is a prime.

242551 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (242521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121275 + 121276.

It is an arithmetic number, because the mean of its divisors is an integer number (121276).

2²⁴²⁵⁵¹ is an apocalyptic number.

242551 is a deficient number, since it is larger than the sum of its proper divisors (1).

242551 is an equidigital number, since it uses as much as digits as its factorization.

242551 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 400, while the sum is 19.

The square root of 242551 is about 492.4946700219. The cubic root of 242551 is about 62.3640565243.

Adding to 242551 its reverse (155242), we get a palindrome (397793).

The spelling of 242551 in words is "two hundred forty-two thousand, five hundred fifty-one".