645454206660 has 24 divisors (see below), whose sum is σ = 1807271778816. Its totient is φ = 172121121760.

The previous prime is 645454206659. The next prime is 645454206713. The reversal of 645454206660 is 66602454546.

It is a super-2 number, since 2×645454206660² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5378784996 + ... + 5378785115.

It is an arithmetic number, because the mean of its divisors is an integer number (75302990784).

Almost surely, 2^645454206660 is an apocalyptic number.

645454206660 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

645454206660 is an abundant number, since it is smaller than the sum of its proper divisors (1161817572156).

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

645454206660 is a wasteful number, since it uses less digits than its factorization.

645454206660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10757570123 (or 10757570121 counting only the distinct ones).

The product of its (nonzero) digits is 4147200, while the sum is 48.

The spelling of 645454206660 in words is "six hundred forty-five billion, four hundred fifty-four million, two hundred six thousand, six hundred sixty".