678997440 has 168 divisors, whose sum is σ = 2547902448. Its totient is φ = 164597760.

The previous prime is 678997411. The next prime is 678997463. The reversal of 678997440 is 44799876.

It is a happy number.

It is a super-2 number, since 2×678997440² = 922075047053107200, which contains 22 as substring.

It is a congruent number.

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, 20964 + ... + 42396.

It is an arithmetic number, because the mean of its divisors is an integer number (15166086).

Almost surely, 2^678997440 is an apocalyptic number.

678997440 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 678997440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1273951224).

678997440 is an abundant number, since it is smaller than the sum of its proper divisors (1868905008).

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

678997440 is a wasteful number, since it uses less digits than its factorization.

678997440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21467 (or 21454 counting only the distinct ones).

The product of its (nonzero) digits is 3048192, while the sum is 54.

The square root of 678997440 is about 26057.5793196529. The cubic root of 678997440 is about 878.9335566189.

The spelling of 678997440 in words is "six hundred seventy-eight million, nine hundred ninety-seven thousand, four hundred forty".