406312195981 has 2 divisors, whose sum is σ = 406312195982. Its totient is φ = 406312195980.

The previous prime is 406312195979. The next prime is 406312196041. The reversal of 406312195981 is 189591213604.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 338647180356 + 67665015625 = 581934^2 + 260125^2 .

It is a cyclic number.

It is not a de Polignac number, because 406312195981 - 2¹ = 406312195979 is a prime.

It is a super-2 number, since 2×406312195981² (a number of 24 digits) contains 22 as substring.

Together with 406312195979, 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 (406312195901) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 203156097990 + 203156097991.

It is an arithmetic number, because the mean of its divisors is an integer number (203156097991).

Almost surely, 2^406312195981 is an apocalyptic number.

It is an amenable number.

406312195981 is a deficient number, since it is larger than the sum of its proper divisors (1).

406312195981 is an equidigital number, since it uses as much as digits as its factorization.

406312195981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 466560, while the sum is 49.

The spelling of 406312195981 in words is "four hundred six billion, three hundred twelve million, one hundred ninety-five thousand, nine hundred eighty-one".