813978 has 24 divisors (see below), whose sum is σ = 1924416. Its totient is φ = 246600.

The previous prime is 813971. The next prime is 813991. The reversal of 813978 is 879318.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 813978.

It is not an unprimeable number, because it can be changed into a prime (813971) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1858 + ... + 2253.

It is an arithmetic number, because the mean of its divisors is an integer number (80184).

2⁸¹³⁹⁷⁸ is an apocalyptic number.

813978 is an abundant number, since it is smaller than the sum of its proper divisors (1110438).

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

813978 is a wasteful number, since it uses less digits than its factorization.

813978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4130 (or 4127 counting only the distinct ones).

The product of its digits is 12096, while the sum is 36.

The square root of 813978 is about 902.2072932536. The cubic root of 813978 is about 93.3693256876.

The spelling of 813978 in words is "eight hundred thirteen thousand, nine hundred seventy-eight".