402144444391 has 4 divisors (see below), whose sum is σ = 404807652784. Its totient is φ = 399481236000.

The previous prime is 402144444343. The next prime is 402144444407. The reversal of 402144444391 is 193444441204.

It is a happy number.

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 402144444391 - 2⁹ = 402144443879 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 (402144444301) 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, 1331603970 + ... + 1331604271.

It is an arithmetic number, because the mean of its divisors is an integer number (101201913196).

Almost surely, 2^402144444391 is an apocalyptic number.

402144444391 is a deficient number, since it is larger than the sum of its proper divisors (2663208393).

402144444391 is a wasteful number, since it uses less digits than its factorization.

402144444391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2663208392.

The product of its (nonzero) digits is 221184, while the sum is 40.

Adding to 402144444391 its reverse (193444441204), we get a palindrome (595588885595).

The spelling of 402144444391 in words is "four hundred two billion, one hundred forty-four million, four hundred forty-four thousand, three hundred ninety-one".