678038981 has 4 divisors (see below), whose sum is σ = 678101964. Its totient is φ = 677976000.

The previous prime is 678038951. The next prime is 678038989. The reversal of 678038981 is 189830876.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 191130625 + 486908356 = 13825^2 + 22066^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-678038981 is a prime.

It is a super-2 number, since 2×678038981² = 919473719511036722, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (678038989) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 10820 + ... + 38381.

It is an arithmetic number, because the mean of its divisors is an integer number (169525491).

Almost surely, 2^678038981 is an apocalyptic number.

It is an amenable number.

678038981 is a deficient number, since it is larger than the sum of its proper divisors (62983).

678038981 is a wasteful number, since it uses less digits than its factorization.

678038981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62982.

The product of its (nonzero) digits is 580608, while the sum is 50.

The square root of 678038981 is about 26039.1816499674. The cubic root of 678038981 is about 878.5198002868.

The spelling of 678038981 in words is "six hundred seventy-eight million, thirty-eight thousand, nine hundred eighty-one".