6420074640 has 160 divisors (see below), whose sum is σ = 23734480896. Its totient is φ = 1403635200.

The previous prime is 6420074629. The next prime is 6420074641. The reversal of 6420074640 is 464700246.

It is a super-2 number, since 2×6420074640² = 82434716766342259200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (6420074641) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 44436 + ... + 121715.

Almost surely, 2^6420074640 is an apocalyptic number.

6420074640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6420074640 is an abundant number, since it is smaller than the sum of its proper divisors (17314406256).

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

6420074640 is a wasteful number, since it uses less digits than its factorization.

6420074640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166197 (or 166191 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 33.

The square root of 6420074640 is about 80125.3682674844. The cubic root of 6420074640 is about 1858.5747203492.

Adding to 6420074640 its reverse (464700246), we get a palindrome (6884774886).

The spelling of 6420074640 in words is "six billion, four hundred twenty million, seventy-four thousand, six hundred forty".