6402881856 has 224 divisors, whose sum is σ = 20103340032. Its totient is φ = 1759979520.

The previous prime is 6402881851. The next prime is 6402881909. The reversal of 6402881856 is 6581882046.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (224).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6402881851) 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, 9457390 + ... + 9458066.

Almost surely, 2^6402881856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 6402881856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (10051670016).

6402881856 is an abundant number, since it is smaller than the sum of its proper divisors (13700458176).

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

6402881856 is a wasteful number, since it uses less digits than its factorization.

6402881856 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 957 (or 947 counting only the distinct ones).

The product of its (nonzero) digits is 737280, while the sum is 48.

The square root of 6402881856 is about 80018.0095728455. The cubic root of 6402881856 is about 1856.9141664322.

The spelling of 6402881856 in words is "six billion, four hundred two million, eight hundred eighty-one thousand, eight hundred fifty-six".