400238169209 has 4 divisors (see below), whose sum is σ = 404735227380. Its totient is φ = 395741111040.

The previous prime is 400238169127. The next prime is 400238169241. The reversal of 400238169209 is 902961832004.

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 27405809209 + 372832360000 = 165547^2 + 610600^2 .

It is a cyclic number.

It is not a de Polignac number, because 400238169209 - 2³⁶ = 331518692473 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 400238169209.

It is not an unprimeable number, because it can be changed into a prime (400238169269) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2248528952 + ... + 2248529129.

It is an arithmetic number, because the mean of its divisors is an integer number (101183806845).

Almost surely, 2^400238169209 is an apocalyptic number.

It is an amenable number.

400238169209 is a deficient number, since it is larger than the sum of its proper divisors (4497058171).

400238169209 is an equidigital number, since it uses as much as digits as its factorization.

400238169209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4497058170.

The product of its (nonzero) digits is 186624, while the sum is 44.

The spelling of 400238169209 in words is "four hundred billion, two hundred thirty-eight million, one hundred sixty-nine thousand, two hundred nine".