402400289 has 2 divisors, whose sum is σ = 402400290. Its totient is φ = 402400288.

The previous prime is 402400279. The next prime is 402400291. The reversal of 402400289 is 982004204.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 225510289 + 176890000 = 15017^2 + 13300^2 .

It is a cyclic number.

It is not a de Polignac number, because 402400289 - 2¹⁶ = 402334753 is a prime.

Together with 402400291, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (402400279) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 201200144 + 201200145.

It is an arithmetic number, because the mean of its divisors is an integer number (201200145).

Almost surely, 2^402400289 is an apocalyptic number.

It is an amenable number.

402400289 is a deficient number, since it is larger than the sum of its proper divisors (1).

402400289 is an equidigital number, since it uses as much as digits as its factorization.

402400289 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 402400289 is about 20059.9174724125. The cubic root of 402400289 is about 738.2771516285.

The spelling of 402400289 in words is "four hundred two million, four hundred thousand, two hundred eighty-nine".