671523840 has 528 divisors, whose sum is σ = 2682388800. Its totient is φ = 153944064.

The previous prime is 671523793. The next prime is 671523883. The reversal of 671523840 is 48325176.

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

It is a junction number, because it is equal to n+sod(n) for n = 671523795 and 671523804.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 11381731 + ... + 11381789.

Almost surely, 2^671523840 is an apocalyptic number.

671523840 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 671523840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1341194400).

671523840 is an abundant number, since it is smaller than the sum of its proper divisors (2010864960).

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

671523840 is a wasteful number, since it uses less digits than its factorization.

671523840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 122 (or 101 counting only the distinct ones).

The product of its (nonzero) digits is 40320, while the sum is 36.

The square root of 671523840 is about 25913.7770307611. Note that the first 3 decimals coincide. The cubic root of 671523840 is about 875.6968989530.

The spelling of 671523840 in words is "six hundred seventy-one million, five hundred twenty-three thousand, eight hundred forty".