978931 has 2 divisors, whose sum is σ = 978932. Its totient is φ = 978930.

The previous prime is 978917. The next prime is 978947. The reversal of 978931 is 139879.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 978931 - 2¹¹ = 976883 is a prime.

It is a super-2 number, since 2×978931² = 1916611805522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (978031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 489465 + 489466.

It is an arithmetic number, because the mean of its divisors is an integer number (489466).

2⁹⁷⁸⁹³¹ is an apocalyptic number.

978931 is a deficient number, since it is larger than the sum of its proper divisors (1).

978931 is an equidigital number, since it uses as much as digits as its factorization.

978931 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13608, while the sum is 37.

The square root of 978931 is about 989.4094198056. The cubic root of 978931 is about 99.2927091914.

The spelling of 978931 in words is "nine hundred seventy-eight thousand, nine hundred thirty-one".