402455561 has 2 divisors, whose sum is σ = 402455562. Its totient is φ = 402455560.

The previous prime is 402455551. The next prime is 402455563. The reversal of 402455561 is 165554204.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 375623161 + 26832400 = 19381^2 + 5180^2 .

It is a cyclic number.

It is not a de Polignac number, because 402455561 - 2¹⁰ = 402454537 is a prime.

It is a Sophie Germain prime.

Together with 402455563, it forms a pair of twin primes.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (402455563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 201227780 + 201227781.

It is an arithmetic number, because the mean of its divisors is an integer number (201227781).

Almost surely, 2^402455561 is an apocalyptic number.

It is an amenable number.

402455561 is a deficient number, since it is larger than the sum of its proper divisors (1).

402455561 is an equidigital number, since it uses as much as digits as its factorization.

402455561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 24000, while the sum is 32.

The square root of 402455561 is about 20061.2950977747. The cubic root of 402455561 is about 738.3109522889.

The spelling of 402455561 in words is "four hundred two million, four hundred fifty-five thousand, five hundred sixty-one".