6440806451 has 4 divisors (see below), whose sum is σ = 6546393504. Its totient is φ = 6335219400.

The previous prime is 6440806423. The next prime is 6440806457. The reversal of 6440806451 is 1546080446.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 6440806451 - 2¹⁴ = 6440790067 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6440806457) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 52793435 + ... + 52793556.

It is an arithmetic number, because the mean of its divisors is an integer number (1636598376).

Almost surely, 2^6440806451 is an apocalyptic number.

6440806451 is a gapful number since it is divisible by the number (61) formed by its first and last digit.

6440806451 is a deficient number, since it is larger than the sum of its proper divisors (105587053).

6440806451 is a wasteful number, since it uses less digits than its factorization.

6440806451 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 105587052.

The product of its (nonzero) digits is 92160, while the sum is 38.

The square root of 6440806451 is about 80254.6350748665. The cubic root of 6440806451 is about 1860.5731508239.

Adding to 6440806451 its reverse (1546080446), we get a palindrome (7986886897).

The spelling of 6440806451 in words is "six billion, four hundred forty million, eight hundred six thousand, four hundred fifty-one".