616244021 has 4 divisors (see below), whose sum is σ = 626346444. Its totient is φ = 606141600.

The previous prime is 616244011. The next prime is 616244047. The reversal of 616244021 is 120442616.

616244021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 181980100 + 434263921 = 13490^2 + 20839^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-616244021 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 (616244011) 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, 5051120 + ... + 5051241.

It is an arithmetic number, because the mean of its divisors is an integer number (156586611).

Almost surely, 2^616244021 is an apocalyptic number.

616244021 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

It is an amenable number.

616244021 is a deficient number, since it is larger than the sum of its proper divisors (10102423).

616244021 is a wasteful number, since it uses less digits than its factorization.

616244021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10102422.

The product of its (nonzero) digits is 2304, while the sum is 26.

The square root of 616244021 is about 24824.2627483678. The cubic root of 616244021 is about 850.9765113974.

Adding to 616244021 its reverse (120442616), we get a palindrome (736686637).

The spelling of 616244021 in words is "six hundred sixteen million, two hundred forty-four thousand, twenty-one".