978181 has 2 divisors, whose sum is σ = 978182. Its totient is φ = 978180.

The previous prime is 978179. The next prime is 978203. The reversal of 978181 is 181879.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 950625 + 27556 = 975^2 + 166^2 .

It is a cyclic number.

It is not a de Polignac number, because 978181 - 2¹ = 978179 is a prime.

It is a super-2 number, since 2×978181² = 1913676137522, which contains 22 as substring.

Together with 978179, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (978151) 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 as a sum of consecutive naturals, namely, 489090 + 489091.

It is an arithmetic number, because the mean of its divisors is an integer number (489091).

2⁹⁷⁸¹⁸¹ is an apocalyptic number.

It is an amenable number.

978181 is a deficient number, since it is larger than the sum of its proper divisors (1).

978181 is an equidigital number, since it uses as much as digits as its factorization.

978181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 4032, while the sum is 34.

The square root of 978181 is about 989.0303332052. The cubic root of 978181 is about 99.2673452798.

The spelling of 978181 in words is "nine hundred seventy-eight thousand, one hundred eighty-one".