20440344377 has 2 divisors, whose sum is σ = 20440344378. Its totient is φ = 20440344376.

The previous prime is 20440344313. The next prime is 20440344391. The reversal of 20440344377 is 77344304402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20250428416 + 189915961 = 142304^2 + 13781^2 .

It is a cyclic number.

It is not a de Polignac number, because 20440344377 - 2⁶ = 20440344313 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20440344377.

It is not a weakly prime, because it can be changed into another prime (20440344307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10220172188 + 10220172189.

It is an arithmetic number, because the mean of its divisors is an integer number (10220172189).

Almost surely, 2^20440344377 is an apocalyptic number.

It is an amenable number.

20440344377 is a deficient number, since it is larger than the sum of its proper divisors (1).

20440344377 is an equidigital number, since it uses as much as digits as its factorization.

20440344377 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 225792, while the sum is 38.

Adding to 20440344377 its reverse (77344304402), we get a palindrome (97784648779).

The spelling of 20440344377 in words is "twenty billion, four hundred forty million, three hundred forty-four thousand, three hundred seventy-seven".