631978 has 8 divisors (see below), whose sum is σ = 997920. Its totient is φ = 299340.

The previous prime is 631937. The next prime is 631979. The reversal of 631978 is 879136.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an Ulam number.

It is not an unprimeable number, because it can be changed into a prime (631979) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8278 + ... + 8353.

It is an arithmetic number, because the mean of its divisors is an integer number (124740).

2⁶³¹⁹⁷⁸ is an apocalyptic number.

631978 is a deficient number, since it is larger than the sum of its proper divisors (365942).

631978 is a wasteful number, since it uses less digits than its factorization.

631978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16652.

The product of its digits is 9072, while the sum is 34.

The square root of 631978 is about 794.9704397020. The cubic root of 631978 is about 85.8158127643.

The spelling of 631978 in words is "six hundred thirty-one thousand, nine hundred seventy-eight".