6448345781 has 2 divisors, whose sum is σ = 6448345782. Its totient is φ = 6448345780.

The previous prime is 6448345697. The next prime is 6448345793. The reversal of 6448345781 is 1875438446.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4365244900 + 2083100881 = 66070^2 + 45641^2 .

It is a cyclic number.

It is not a de Polignac number, because 6448345781 - 2¹⁴ = 6448329397 is a prime.

It is a super-2 number, since 2×6448345781² = 83162326622680999922, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6448345081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3224172890 + 3224172891.

It is an arithmetic number, because the mean of its divisors is an integer number (3224172891).

Almost surely, 2^6448345781 is an apocalyptic number.

It is an amenable number.

6448345781 is a deficient number, since it is larger than the sum of its proper divisors (1).

6448345781 is an equidigital number, since it uses as much as digits as its factorization.

6448345781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2580480, while the sum is 50.

The square root of 6448345781 is about 80301.5926429856. The cubic root of 6448345781 is about 1861.2988366169.

The spelling of 6448345781 in words is "six billion, four hundred forty-eight million, three hundred forty-five thousand, seven hundred eighty-one".