6440005373 has 2 divisors, whose sum is σ = 6440005374. Its totient is φ = 6440005372.

The previous prime is 6440005349. The next prime is 6440005387. The reversal of 6440005373 is 3735000446.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4553145529 + 1886859844 = 67477^2 + 43438^2 .

It is a cyclic number.

It is not a de Polignac number, because 6440005373 - 2⁶ = 6440005309 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6440005393) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3220002686 + 3220002687.

It is an arithmetic number, because the mean of its divisors is an integer number (3220002687).

Almost surely, 2^6440005373 is an apocalyptic number.

It is an amenable number.

6440005373 is a deficient number, since it is larger than the sum of its proper divisors (1).

6440005373 is an equidigital number, since it uses as much as digits as its factorization.

6440005373 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 30240, while the sum is 32.

The square root of 6440005373 is about 80249.6440677465. The cubic root of 6440005373 is about 1860.4960111041.

The spelling of 6440005373 in words is "six billion, four hundred forty million, five thousand, three hundred seventy-three".