671209198920 has 640 divisors, whose sum is σ = 2511125971200. Its totient is φ = 159730735104.

The previous prime is 671209198861. The next prime is 671209198921. The reversal of 671209198920 is 29891902176.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (671209198921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 260258191 + ... + 260260769.

It is an arithmetic number, because the mean of its divisors is an integer number (3923634330).

Almost surely, 2^671209198920 is an apocalyptic number.

671209198920 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 671209198920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1255562985600).

671209198920 is an abundant number, since it is smaller than the sum of its proper divisors (1839916772280).

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

671209198920 is a wasteful number, since it uses less digits than its factorization.

671209198920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2819 (or 2806 counting only the distinct ones).

The product of its (nonzero) digits is 979776, while the sum is 54.

The spelling of 671209198920 in words is "six hundred seventy-one billion, two hundred nine million, one hundred ninety-eight thousand, nine hundred twenty".