240121621 has 4 divisors (see below), whose sum is σ = 240156972. Its totient is φ = 240086272.

The previous prime is 240121619. The next prime is 240121631. The reversal of 240121621 is 126121042.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 126121042 = 2 ⋅63060521.

It can be written as a sum of positive squares in 2 ways, for example, as 115799121 + 124322500 = 10761^2 + 11150^2 .

It is a cyclic number.

It is not a de Polignac number, because 240121621 - 2¹ = 240121619 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 (240121631) 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, 3916 + ... + 22261.

It is an arithmetic number, because the mean of its divisors is an integer number (60039243).

Almost surely, 2^240121621 is an apocalyptic number.

It is an amenable number.

240121621 is a deficient number, since it is larger than the sum of its proper divisors (35351).

240121621 is an equidigital number, since it uses as much as digits as its factorization.

240121621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35350.

The product of its (nonzero) digits is 192, while the sum is 19.

The square root of 240121621 is about 15495.8581885612. The cubic root of 240121621 is about 621.5514569984.

Adding to 240121621 its reverse (126121042), we get a palindrome (366242663).

The spelling of 240121621 in words is "two hundred forty million, one hundred twenty-one thousand, six hundred twenty-one".