6440253420 has 48 divisors (see below), whose sum is σ = 18042363360. Its totient is φ = 1716481536.

The previous prime is 6440253419. The next prime is 6440253427. The reversal of 6440253420 is 243520446.

It is a super-2 number, since 2×6440253420² = 82953728227643392800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is not an unprimeable number, because it can be changed into a prime (6440253427) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 88216 + ... + 143744.

It is an arithmetic number, because the mean of its divisors is an integer number (375882570).

Almost surely, 2^6440253420 is an apocalyptic number.

6440253420 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6440253420 is an abundant number, since it is smaller than the sum of its proper divisors (11602109940).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6440253420 is a wasteful number, since it uses less digits than its factorization.

6440253420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57474 (or 57472 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 30.

The square root of 6440253420 is about 80251.1895238943. The cubic root of 6440253420 is about 1860.5198974470.

Adding to 6440253420 its reverse (243520446), we get a palindrome (6683773866).

The spelling of 6440253420 in words is "six billion, four hundred forty million, two hundred fifty-three thousand, four hundred twenty".