242615221 has 4 divisors (see below), whose sum is σ = 242687500. Its totient is φ = 242542944.

The previous prime is 242615209. The next prime is 242615227. The reversal of 242615221 is 122516242.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 21022225 + 221592996 = 4585^2 + 14886^2 .

It is a cyclic number.

It is not a de Polignac number, because 242615221 - 2²⁷ = 108397493 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 (242615227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30846 + ... + 37903.

It is an arithmetic number, because the mean of its divisors is an integer number (60671875).

Almost surely, 2^242615221 is an apocalyptic number.

It is an amenable number.

242615221 is a deficient number, since it is larger than the sum of its proper divisors (72279).

242615221 is an equidigital number, since it uses as much as digits as its factorization.

242615221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 72278.

The product of its digits is 1920, while the sum is 25.

The square root of 242615221 is about 15576.1105864076. The cubic root of 242615221 is about 623.6956014851.

The spelling of 242615221 in words is "two hundred forty-two million, six hundred fifteen thousand, two hundred twenty-one".