6401870556 has 12 divisors (see below), whose sum is σ = 14937697992. Its totient is φ = 2133956848.

The previous prime is 6401870551. The next prime is 6401870599. The reversal of 6401870556 is 6550781046.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6401870551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 266744595 + ... + 266744618.

It is an arithmetic number, because the mean of its divisors is an integer number (1244808166).

Almost surely, 2^6401870556 is an apocalyptic number.

It is an amenable number.

6401870556 is an abundant number, since it is smaller than the sum of its proper divisors (8535827436).

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

6401870556 is a wasteful number, since it uses less digits than its factorization.

6401870556 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 533489220 (or 533489218 counting only the distinct ones).

The product of its (nonzero) digits is 201600, while the sum is 42.

The square root of 6401870556 is about 80011.6901208817. The cubic root of 6401870556 is about 1856.8163981556.

The spelling of 6401870556 in words is "six billion, four hundred one million, eight hundred seventy thousand, five hundred fifty-six".