402144321 has 4 divisors (see below), whose sum is σ = 536192432. Its totient is φ = 268096212.

The previous prime is 402144319. The next prime is 402144341. The reversal of 402144321 is 123441204.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 402144321 - 2¹ = 402144319 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (402144341) 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, 67024051 + ... + 67024056.

It is an arithmetic number, because the mean of its divisors is an integer number (134048108).

Almost surely, 2^402144321 is an apocalyptic number.

It is an amenable number.

402144321 is a deficient number, since it is larger than the sum of its proper divisors (134048111).

402144321 is a wasteful number, since it uses less digits than its factorization.

402144321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134048110.

The product of its (nonzero) digits is 768, while the sum is 21.

The square root of 402144321 is about 20053.5363714234. The cubic root of 402144321 is about 738.1205783402.

Adding to 402144321 its reverse (123441204), we get a palindrome (525585525).

The spelling of 402144321 in words is "four hundred two million, one hundred forty-four thousand, three hundred twenty-one".