240242020421 has 4 divisors (see below), whose sum is σ = 258722175852. Its totient is φ = 221761864992.

The previous prime is 240242020411. The next prime is 240242020457. The reversal of 240242020421 is 124020242042.

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 14701562500 + 225540457921 = 121250^2 + 474911^2 .

It is a cyclic number.

It is not a de Polignac number, because 240242020421 - 2¹⁰ = 240242019397 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (240242020411) 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, 9240077696 + ... + 9240077721.

It is an arithmetic number, because the mean of its divisors is an integer number (64680543963).

Almost surely, 2^240242020421 is an apocalyptic number.

It is an amenable number.

240242020421 is a deficient number, since it is larger than the sum of its proper divisors (18480155431).

240242020421 is a wasteful number, since it uses less digits than its factorization.

240242020421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18480155430.

The product of its (nonzero) digits is 2048, while the sum is 23.

Adding to 240242020421 its reverse (124020242042), we get a palindrome (364262262463).

The spelling of 240242020421 in words is "two hundred forty billion, two hundred forty-two million, twenty thousand, four hundred twenty-one".