6420509444 has 12 divisors (see below), whose sum is σ = 11254591068. Its totient is φ = 3204912000.

The previous prime is 6420509437. The next prime is 6420509449. The reversal of 6420509444 is 4449050246.

It can be written as a sum of positive squares in 2 ways, for example, as 5329000000 + 1091509444 = 73000^2 + 33038^2 .

It is a hoax number, since the sum of its digits (38) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 6420509398 and 6420509407.

It is not an unprimeable number, because it can be changed into a prime (6420509449) 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, 1332977 + ... + 1337784.

It is an arithmetic number, because the mean of its divisors is an integer number (937882589).

Almost surely, 2^6420509444 is an apocalyptic number.

It is an amenable number.

6420509444 is a deficient number, since it is larger than the sum of its proper divisors (4834081624).

6420509444 is a wasteful number, since it uses less digits than its factorization.

6420509444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2671366 (or 2671364 counting only the distinct ones).

The product of its (nonzero) digits is 138240, while the sum is 38.

The square root of 6420509444 is about 80128.0814945672. The cubic root of 6420509444 is about 1858.6166771553.

The spelling of 6420509444 in words is "six billion, four hundred twenty million, five hundred nine thousand, four hundred forty-four".