6404428020 has 48 divisors (see below), whose sum is σ = 18987248448. Its totient is φ = 1607385600.

The previous prime is 6404427979. The next prime is 6404428027. The reversal of 6404428020 is 208244046.

It is a super-2 number, since 2×6404428020² = 82033396526722240800, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6404428027) 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, 3138406 + ... + 3140445.

It is an arithmetic number, because the mean of its divisors is an integer number (395567676).

Almost surely, 2^6404428020 is an apocalyptic number.

6404428020 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6404428020 is an abundant number, since it is smaller than the sum of its proper divisors (12582820428).

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

6404428020 is a wasteful number, since it uses less digits than its factorization.

6404428020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6278880 (or 6278878 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 30.

The square root of 6404428020 is about 80027.6703397019. The cubic root of 6404428020 is about 1857.0636232355.

The spelling of 6404428020 in words is "six billion, four hundred four million, four hundred twenty-eight thousand, twenty".