671686020 has 168 divisors, whose sum is σ = 2207894976. Its totient is φ = 171243072.

The previous prime is 671685983. The next prime is 671686051. The reversal of 671686020 is 20686176.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 334339 + ... + 336341.

It is an arithmetic number, because the mean of its divisors is an integer number (13142232).

Almost surely, 2^671686020 is an apocalyptic number.

671686020 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 671686020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1103947488).

671686020 is an abundant number, since it is smaller than the sum of its proper divisors (1536208956).

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

671686020 is a wasteful number, since it uses less digits than its factorization.

671686020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2053 (or 2036 counting only the distinct ones).

The product of its (nonzero) digits is 24192, while the sum is 36.

The square root of 671686020 is about 25916.9060653466. The cubic root of 671686020 is about 875.7673899185.

The spelling of 671686020 in words is "six hundred seventy-one million, six hundred eighty-six thousand, twenty".