671938920 has 96 divisors (see below), whose sum is σ = 2196628200. Its totient is φ = 178131456.

The previous prime is 671938909. The next prime is 671938979. The reversal of 671938920 is 29839176.

It can be written as a sum of positive squares in 4 ways, for example, as 631717956 + 40220964 = 25134^2 + 6342^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 56886 + ... + 67674.

Almost surely, 2^671938920 is an apocalyptic number.

671938920 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 671938920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1098314100).

671938920 is an abundant number, since it is smaller than the sum of its proper divisors (1524689280).

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

671938920 is a wasteful number, since it uses less digits than its factorization.

671938920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10979 (or 10972 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 45.

The square root of 671938920 is about 25921.7846607829. The cubic root of 671938920 is about 875.8772893730.

The spelling of 671938920 in words is "six hundred seventy-one million, nine hundred thirty-eight thousand, nine hundred twenty".