396143981 has 2 divisors, whose sum is σ = 396143982. Its totient is φ = 396143980.

The previous prime is 396143963. The next prime is 396144029. The reversal of 396143981 is 189341693.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 298944100 + 97199881 = 17290^2 + 9859^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-396143981 is a prime.

It is a super-2 number, since 2×396143981² = 313860107365056722, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (396143921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 198071990 + 198071991.

It is an arithmetic number, because the mean of its divisors is an integer number (198071991).

Almost surely, 2^396143981 is an apocalyptic number.

It is an amenable number.

396143981 is a deficient number, since it is larger than the sum of its proper divisors (1).

396143981 is an equidigital number, since it uses as much as digits as its factorization.

396143981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 139968, while the sum is 44.

The square root of 396143981 is about 19903.3660720995. The cubic root of 396143981 is about 734.4310348334.

The spelling of 396143981 in words is "three hundred ninety-six million, one hundred forty-three thousand, nine hundred eighty-one".