667721343273260 has 24 divisors (see below), whose sum is σ = 1402283818175856. Its totient is φ = 267075394966080.

The previous prime is 667721343273239. The next prime is 667721343273263. The reversal of 667721343273260 is 62372343127766.

It is a self number, because there is not a number n which added to its sum of digits gives 667721343273260.

It is not an unprimeable number, because it can be changed into a prime (667721343273263) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 820979831 + ... + 821792750.

It is an arithmetic number, because the mean of its divisors is an integer number (58428492423994).

Almost surely, 2^{667721343273260} is an apocalyptic number.

It is an amenable number.

667721343273260 is an abundant number, since it is smaller than the sum of its proper divisors (734562474902596).

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

667721343273260 is a wasteful number, since it uses less digits than its factorization.

667721343273260 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1642792913 (or 1642792911 counting only the distinct ones).

The product of its (nonzero) digits is 64012032, while the sum is 59.

The spelling of 667721343273260 in words is "six hundred sixty-seven trillion, seven hundred twenty-one billion, three hundred forty-three million, two hundred seventy-three thousand, two hundred sixty".