402440420423 has 4 divisors (see below), whose sum is σ = 407534603040. Its totient is φ = 397346237808.

The previous prime is 402440420399. The next prime is 402440420461. The reversal of 402440420423 is 324024044204.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-402440420423 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (402440470423) 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, 2547091190 + ... + 2547091347.

It is an arithmetic number, because the mean of its divisors is an integer number (101883650760).

Almost surely, 2^402440420423 is an apocalyptic number.

402440420423 is a deficient number, since it is larger than the sum of its proper divisors (5094182617).

402440420423 is an equidigital number, since it uses as much as digits as its factorization.

402440420423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5094182616.

The product of its (nonzero) digits is 24576, while the sum is 29.

Adding to 402440420423 its reverse (324024044204), we get a palindrome (726464464627).

The spelling of 402440420423 in words is "four hundred two billion, four hundred forty million, four hundred twenty thousand, four hundred twenty-three".