645669466266 has 128 divisors (see below), whose sum is σ = 1475927101440. Its totient is φ = 186510464000.

The previous prime is 645669466261. The next prime is 645669466279. The reversal of 645669466266 is 662664966546.

It is a Harshad number since it is a multiple of its sum of digits (66).

It is a junction number, because it is equal to n+sod(n) for n = 645669466197 and 645669466206.

It is not an unprimeable number, because it can be changed into a prime (645669466261) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 56876491 + ... + 56887841.

It is an arithmetic number, because the mean of its divisors is an integer number (11530680480).

Almost surely, 2^645669466266 is an apocalyptic number.

645669466266 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 645669466266, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (737963550720).

645669466266 is an abundant number, since it is smaller than the sum of its proper divisors (830257635174).

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

645669466266 is a wasteful number, since it uses less digits than its factorization.

645669466266 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11772.

The product of its digits is 403107840, while the sum is 66.

The spelling of 645669466266 in words is "six hundred forty-five billion, six hundred sixty-nine million, four hundred sixty-six thousand, two hundred sixty-six".