634163281 has 2 divisors, whose sum is σ = 634163282. Its totient is φ = 634163280.

The previous prime is 634163279. The next prime is 634163287. The reversal of 634163281 is 182361436.

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., 474368400 + 159794881 = 21780^2 + 12641^2 .

It is a cyclic number.

It is not a de Polignac number, because 634163281 - 2¹ = 634163279 is a prime.

It is a super-2 number, since 2×634163281² = 804326133937369922, which contains 22 as substring.

Together with 634163279, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (634163287) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 317081640 + 317081641.

It is an arithmetic number, because the mean of its divisors is an integer number (317081641).

Almost surely, 2^634163281 is an apocalyptic number.

It is an amenable number.

634163281 is a deficient number, since it is larger than the sum of its proper divisors (1).

634163281 is an equidigital number, since it uses as much as digits as its factorization.

634163281 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20736, while the sum is 34.

The square root of 634163281 is about 25182.5987737565. The cubic root of 634163281 is about 859.1461152403.

The spelling of 634163281 in words is "six hundred thirty-four million, one hundred sixty-three thousand, two hundred eighty-one".