671645579520 has 144 divisors (see below), whose sum is σ = 2194953913152. Its totient is φ = 174940200960.

The previous prime is 671645579489. The next prime is 671645579543. The reversal of 671645579520 is 25975546176.

It is a super-2 number, since 2×671645579520² (a number of 24 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1868691 + ... + 2198930.

It is an arithmetic number, because the mean of its divisors is an integer number (15242735508).

Almost surely, 2^671645579520 is an apocalyptic number.

671645579520 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

671645579520 is an abundant number, since it is smaller than the sum of its proper divisors (1523308333632).

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

671645579520 is a wasteful number, since it uses less digits than its factorization.

671645579520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4067688 (or 4067674 counting only the distinct ones).

The product of its (nonzero) digits is 15876000, while the sum is 57.

The spelling of 671645579520 in words is "six hundred seventy-one billion, six hundred forty-five million, five hundred seventy-nine thousand, five hundred twenty".