242515391 has 2 divisors, whose sum is σ = 242515392. Its totient is φ = 242515390.

The previous prime is 242515367. The next prime is 242515499. The reversal of 242515391 is 193515242.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-242515391 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (242515331) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121257695 + 121257696.

It is an arithmetic number, because the mean of its divisors is an integer number (121257696).

Almost surely, 2^242515391 is an apocalyptic number.

242515391 is a deficient number, since it is larger than the sum of its proper divisors (1).

242515391 is an equidigital number, since it uses as much as digits as its factorization.

242515391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10800, while the sum is 32.

The square root of 242515391 is about 15572.9056697843. The cubic root of 242515391 is about 623.6100447840.

The spelling of 242515391 in words is "two hundred forty-two million, five hundred fifteen thousand, three hundred ninety-one".