240042721 has 2 divisors, whose sum is σ = 240042722. Its totient is φ = 240042720.

The previous prime is 240042679. The next prime is 240042731. The reversal of 240042721 is 127240042.

It is a happy number.

240042721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 221861025 + 18181696 = 14895^2 + 4264^2 .

It is a cyclic number.

It is not a de Polignac number, because 240042721 - 2²³ = 231654113 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 240042692 and 240042701.

It is not a weakly prime, because it can be changed into another prime (240042731) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 120021360 + 120021361.

It is an arithmetic number, because the mean of its divisors is an integer number (120021361).

Almost surely, 2^240042721 is an apocalyptic number.

It is an amenable number.

240042721 is a deficient number, since it is larger than the sum of its proper divisors (1).

240042721 is an equidigital number, since it uses as much as digits as its factorization.

240042721 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 896, while the sum is 22.

The square root of 240042721 is about 15493.3121378226. The cubic root of 240042721 is about 621.4833723586.

Adding to 240042721 its reverse (127240042), we get a palindrome (367282763).

The spelling of 240042721 in words is "two hundred forty million, forty-two thousand, seven hundred twenty-one".