618240421 has 2 divisors, whose sum is σ = 618240422. Its totient is φ = 618240420.

The previous prime is 618240367. The next prime is 618240439. The reversal of 618240421 is 124042816.

618240421 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., 614296225 + 3944196 = 24785^2 + 1986^2 .

It is a cyclic number.

It is not a de Polignac number, because 618240421 - 2¹¹ = 618238373 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 618240421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (618240481) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 309120210 + 309120211.

It is an arithmetic number, because the mean of its divisors is an integer number (309120211).

Almost surely, 2^618240421 is an apocalyptic number.

It is an amenable number.

618240421 is a deficient number, since it is larger than the sum of its proper divisors (1).

618240421 is an equidigital number, since it uses as much as digits as its factorization.

618240421 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3072, while the sum is 28.

The square root of 618240421 is about 24864.4408945787. The cubic root of 618240421 is about 851.8944693034.

The spelling of 618240421 in words is "six hundred eighteen million, two hundred forty thousand, four hundred twenty-one".