242749861 has 4 divisors (see below), whose sum is σ = 243128032. Its totient is φ = 242371692.

The previous prime is 242749853. The next prime is 242749873. The reversal of 242749861 is 168947242.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 168947242 = 2 ⋅84473621.

It is a cyclic number.

It is not a de Polignac number, because 242749861 - 2³ = 242749853 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (242749841) 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 in 3 ways as a sum of consecutive naturals, for example, 188121 + ... + 189406.

It is an arithmetic number, because the mean of its divisors is an integer number (60782008).

Almost surely, 2^242749861 is an apocalyptic number.

It is an amenable number.

242749861 is a deficient number, since it is larger than the sum of its proper divisors (378171).

242749861 is an equidigital number, since it uses as much as digits as its factorization.

242749861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 378170.

The product of its digits is 193536, while the sum is 43.

The square root of 242749861 is about 15580.4319901600. The cubic root of 242749861 is about 623.8109540260.

The spelling of 242749861 in words is "two hundred forty-two million, seven hundred forty-nine thousand, eight hundred sixty-one".