6421031556 has 12 divisors (see below), whose sum is σ = 14982406992. Its totient is φ = 2140343848.

The previous prime is 6421031521. The next prime is 6421031579. The reversal of 6421031556 is 6551301246.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×6421031556² = 82459292486295562272, which contains 22 as substring.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 267542970 + ... + 267542993.

It is an arithmetic number, because the mean of its divisors is an integer number (1248533916).

Almost surely, 2^6421031556 is an apocalyptic number.

It is an amenable number.

6421031556 is an abundant number, since it is smaller than the sum of its proper divisors (8561375436).

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

6421031556 is a wasteful number, since it uses less digits than its factorization.

6421031556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 535085970 (or 535085968 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 33.

The square root of 6421031556 is about 80131.3394122424. The cubic root of 6421031556 is about 1858.6670563230.

The spelling of 6421031556 in words is "six billion, four hundred twenty-one million, thirty-one thousand, five hundred fifty-six".