646474711128 has 128 divisors (see below), whose sum is σ = 1793672294400. Its totient is φ = 193126957056.

The previous prime is 646474711097. The next prime is 646474711133. The reversal of 646474711128 is 821117474646.

It is a Harshad number since it is a multiple of its sum of digits (51).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1938168 + ... + 2247096.

It is an arithmetic number, because the mean of its divisors is an integer number (14013064800).

Almost surely, 2^646474711128 is an apocalyptic number.

646474711128 is a gapful number since it is divisible by the number (68) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646474711128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (896836147200).

646474711128 is an abundant number, since it is smaller than the sum of its proper divisors (1147197583272).

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

646474711128 is a wasteful number, since it uses less digits than its factorization.

646474711128 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 309201 (or 309197 counting only the distinct ones).

The product of its digits is 1806336, while the sum is 51.

The spelling of 646474711128 in words is "six hundred forty-six billion, four hundred seventy-four million, seven hundred eleven thousand, one hundred twenty-eight".