244778621 has 2 divisors, whose sum is σ = 244778622. Its totient is φ = 244778620.

The previous prime is 244778617. The next prime is 244778623. The reversal of 244778621 is 126877442.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 231192025 + 13586596 = 15205^2 + 3686^2 .

It is a cyclic number.

It is not a de Polignac number, because 244778621 - 2² = 244778617 is a prime.

Together with 244778623, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (244778623) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 122389310 + 122389311.

It is an arithmetic number, because the mean of its divisors is an integer number (122389311).

Almost surely, 2^244778621 is an apocalyptic number.

It is an amenable number.

244778621 is a deficient number, since it is larger than the sum of its proper divisors (1).

244778621 is an equidigital number, since it uses as much as digits as its factorization.

244778621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 150528, while the sum is 41.

The square root of 244778621 is about 15645.4025515485. The cubic root of 244778621 is about 625.5439497059.

The spelling of 244778621 in words is "two hundred forty-four million, seven hundred seventy-eight thousand, six hundred twenty-one".