427679981 has 2 divisors, whose sum is σ = 427679982. Its totient is φ = 427679980.

The previous prime is 427679971. The next prime is 427680017. The reversal of 427679981 is 189976724.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 273075625 + 154604356 = 16525^2 + 12434^2 .

It is a cyclic number.

It is not a de Polignac number, because 427679981 - 2¹⁰ = 427678957 is a prime.

It is a super-2 number, since 2×427679981² = 365820332296320722, 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 (427679971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 213839990 + 213839991.

It is an arithmetic number, because the mean of its divisors is an integer number (213839991).

Almost surely, 2^427679981 is an apocalyptic number.

It is an amenable number.

427679981 is a deficient number, since it is larger than the sum of its proper divisors (1).

427679981 is an equidigital number, since it uses as much as digits as its factorization.

427679981 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1524096, while the sum is 53.

The square root of 427679981 is about 20680.4250681653. The cubic root of 427679981 is about 753.4243302292.

The spelling of 427679981 in words is "four hundred twenty-seven million, six hundred seventy-nine thousand, nine hundred eighty-one".