400240243 has 4 divisors (see below), whose sum is σ = 431027968. Its totient is φ = 369452520.

The previous prime is 400240219. The next prime is 400240249. The reversal of 400240243 is 342042004.

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

It is a cyclic number.

It is not a de Polignac number, because 400240243 - 2¹³ = 400232051 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 400240243.

It is not an unprimeable number, because it can be changed into a prime (400240249) 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, 15393843 + ... + 15393868.

It is an arithmetic number, because the mean of its divisors is an integer number (107756992).

Almost surely, 2^400240243 is an apocalyptic number.

400240243 is a deficient number, since it is larger than the sum of its proper divisors (30787725).

400240243 is a wasteful number, since it uses less digits than its factorization.

400240243 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30787724.

The product of its (nonzero) digits is 768, while the sum is 19.

The square root of 400240243 is about 20006.0051734473. The cubic root of 400240243 is about 736.9537806692.

Adding to 400240243 its reverse (342042004), we get a palindrome (742282247).

The spelling of 400240243 in words is "four hundred million, two hundred forty thousand, two hundred forty-three".