673985556 has 144 divisors (see below), whose sum is σ = 1881835200. Its totient is φ = 208516032.

The previous prime is 673985551. The next prime is 673985561. The reversal of 673985556 is 655589376.

673985556 is a `hidden beast` number, since 6 + 7 + 3 + 9 + 85 + 556 = 666.

It is an interprime number because it is at equal distance from previous prime (673985551) and next prime (673985561).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (673985551) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2300146 + ... + 2300438.

It is an arithmetic number, because the mean of its divisors is an integer number (13068300).

Almost surely, 2^673985556 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 673985556, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (940917600).

673985556 is an abundant number, since it is smaller than the sum of its proper divisors (1207849644).

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

673985556 is a wasteful number, since it uses less digits than its factorization.

673985556 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 403 (or 376 counting only the distinct ones).

The product of its digits is 6804000, while the sum is 54.

The square root of 673985556 is about 25961.2317889579. The cubic root of 673985556 is about 876.7656563578.

It can be divided in two parts, 673985 and 556, that added together give a triangular number (674541 = T₁₁₆₁).

The spelling of 673985556 in words is "six hundred seventy-three million, nine hundred eighty-five thousand, five hundred fifty-six".