61744444621 has 2 divisors, whose sum is σ = 61744444622. Its totient is φ = 61744444620.

The previous prime is 61744444579. The next prime is 61744444639. The reversal of 61744444621 is 12644444716.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 51897851721 + 9846592900 = 227811^2 + 99230^2 .

It is a cyclic number.

It is not a de Polignac number, because 61744444621 - 2⁷ = 61744444493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61744444651) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30872222310 + 30872222311.

It is an arithmetic number, because the mean of its divisors is an integer number (30872222311).

Almost surely, 2^61744444621 is an apocalyptic number.

It is an amenable number.

61744444621 is a deficient number, since it is larger than the sum of its proper divisors (1).

61744444621 is an equidigital number, since it uses as much as digits as its factorization.

61744444621 is an evil number, because the sum of its binary digits is even.

The product of its digits is 516096, while the sum is 43.

The spelling of 61744444621 in words is "sixty-one billion, seven hundred forty-four million, four hundred forty-four thousand, six hundred twenty-one".