402056209 has 4 divisors (see below), whose sum is σ = 411862500. Its totient is φ = 392249920.

The previous prime is 402056191. The next prime is 402056231. The reversal of 402056209 is 902650204.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 188457984 + 213598225 = 13728^2 + 14615^2 .

It is a cyclic number.

It is not a de Polignac number, because 402056209 - 2⁵ = 402056177 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (402056269) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4903084 + ... + 4903165.

It is an arithmetic number, because the mean of its divisors is an integer number (102965625).

Almost surely, 2^402056209 is an apocalyptic number.

It is an amenable number.

402056209 is a deficient number, since it is larger than the sum of its proper divisors (9806291).

402056209 is an equidigital number, since it uses as much as digits as its factorization.

402056209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9806290.

The product of its (nonzero) digits is 4320, while the sum is 28.

The square root of 402056209 is about 20051.3393318252. The cubic root of 402056209 is about 738.0666656630.

The spelling of 402056209 in words is "four hundred two million, fifty-six thousand, two hundred nine".