646865534522280 has 384 divisors, whose sum is σ = 2054993244071040. Its totient is φ = 162792552038400.

The previous prime is 646865534522213. The next prime is 646865534522299. The reversal of 646865534522280 is 82225435568646.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 11664244312 + ... + 11664299768.

It is an arithmetic number, because the mean of its divisors is an integer number (5351544906435).

Almost surely, 2^{646865534522280} is an apocalyptic number.

646865534522280 is a gapful number since it is divisible by the number (60) 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 646865534522280, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1027496622035520).

646865534522280 is an abundant number, since it is smaller than the sum of its proper divisors (1408127709548760).

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

646865534522280 is a wasteful number, since it uses less digits than its factorization.

646865534522280 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58041 (or 58006 counting only the distinct ones).

The product of its (nonzero) digits is 663552000, while the sum is 66.

The spelling of 646865534522280 in words is "six hundred forty-six trillion, eight hundred sixty-five billion, five hundred thirty-four million, five hundred twenty-two thousand, two hundred eighty".