404668981 has 2 divisors, whose sum is σ = 404668982. Its totient is φ = 404668980.

The previous prime is 404668961. The next prime is 404668993. The reversal of 404668981 is 189866404.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 391644100 + 13024881 = 19790^2 + 3609^2 .

It is a cyclic number.

It is not a de Polignac number, because 404668981 - 2¹⁹ = 404144693 is a prime.

It is a super-2 number, since 2×404668981² = 327513968367156722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (404668961) 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 as a sum of consecutive naturals, namely, 202334490 + 202334491.

It is an arithmetic number, because the mean of its divisors is an integer number (202334491).

Almost surely, 2^404668981 is an apocalyptic number.

It is an amenable number.

404668981 is a deficient number, since it is larger than the sum of its proper divisors (1).

404668981 is an equidigital number, since it uses as much as digits as its factorization.

404668981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 331776, while the sum is 46.

The square root of 404668981 is about 20116.3858831551. The cubic root of 404668981 is about 739.6619962328.

The spelling of 404668981 in words is "four hundred four million, six hundred sixty-eight thousand, nine hundred eighty-one".