400243313 has 8 divisors (see below), whose sum is σ = 404966760. Its totient is φ = 395539200.

The previous prime is 400243289. The next prime is 400243331. The reversal of 400243313 is 313342004.

It can be written as a sum of positive squares in 4 ways, for example, as 138839089 + 261404224 = 11783^2 + 16168^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-400243313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (400243373) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 39131 + ... + 48287.

It is an arithmetic number, because the mean of its divisors is an integer number (50620845).

Almost surely, 2^400243313 is an apocalyptic number.

It is an amenable number.

400243313 is a deficient number, since it is larger than the sum of its proper divisors (4723447).

400243313 is a wasteful number, since it uses less digits than its factorization.

400243313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9667.

The product of its (nonzero) digits is 864, while the sum is 20.

The square root of 400243313 is about 20006.0819002622. The cubic root of 400243313 is about 736.9556649061.

Adding to 400243313 its reverse (313342004), we get a palindrome (713585317).

The spelling of 400243313 in words is "four hundred million, two hundred forty-three thousand, three hundred thirteen".