240621 has 4 divisors (see below), whose sum is σ = 320832. Its totient is φ = 160412.

The previous prime is 240607. The next prime is 240623. The reversal of 240621 is 126042.

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.

It is a cyclic number.

It is not a de Polignac number, because 240621 - 2⁵ = 240589 is a prime.

It is a D-number.

It is a self number, because there is not a number n which added to its sum of digits gives 240621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (240623) 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, 40101 + ... + 40106.

It is an arithmetic number, because the mean of its divisors is an integer number (80208).

2²⁴⁰⁶²¹ is an apocalyptic number.

It is an amenable number.

240621 is a deficient number, since it is larger than the sum of its proper divisors (80211).

240621 is an equidigital number, since it uses as much as digits as its factorization.

240621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80210.

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 240621 is about 490.5313445642. The cubic root of 240621 is about 62.1982037164.

Adding to 240621 its reverse (126042), we get a palindrome (366663).

It can be divided in two parts, 240 and 621, that added together give a triangular number (861 = T₄₁).

The spelling of 240621 in words is "two hundred forty thousand, six hundred twenty-one".