256743500662220 has 96 divisors (see below), whose sum is σ = 633572879365440. Its totient is φ = 86158881423360.

The previous prime is 256743500662217. The next prime is 256743500662237. The reversal of 256743500662220 is 22266005347652.

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, 1069676 + ... + 22685484.

It is an arithmetic number, because the mean of its divisors is an integer number (6599717493390).

Almost surely, 2^{256743500662220} is an apocalyptic number.

256743500662220 is a gapful number since it is divisible by the number (20) 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 256743500662220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (316786439682720).

256743500662220 is an abundant number, since it is smaller than the sum of its proper divisors (376829378703220).

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

256743500662220 is a wasteful number, since it uses less digits than its factorization.

256743500662220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21619995 (or 21619993 counting only the distinct ones).

The product of its (nonzero) digits is 7257600, while the sum is 50.

The spelling of 256743500662220 in words is "two hundred fifty-six trillion, seven hundred forty-three billion, five hundred million, six hundred sixty-two thousand, two hundred twenty".