400006623 has 4 divisors (see below), whose sum is σ = 533342168. Its totient is φ = 266671080.

The previous prime is 400006603. The next prime is 400006643. The reversal of 400006623 is 326600004.

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

It is an interprime number because it is at equal distance from previous prime (400006603) and next prime (400006643).

It is not a de Polignac number, because 400006623 - 2⁹ = 400006111 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 400006623.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400006603) 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, 66667768 + ... + 66667773.

It is an arithmetic number, because the mean of its divisors is an integer number (133335542).

Almost surely, 2^400006623 is an apocalyptic number.

400006623 is a deficient number, since it is larger than the sum of its proper divisors (133335545).

400006623 is a wasteful number, since it uses less digits than its factorization.

400006623 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133335544.

The product of its (nonzero) digits is 864, while the sum is 21.

The square root of 400006623 is about 20000.1655743146. The cubic root of 400006623 is about 736.8103662624.

Adding to 400006623 its reverse (326600004), we get a palindrome (726606627).

The spelling of 400006623 in words is "four hundred million, six thousand, six hundred twenty-three".