402143221 has 4 divisors (see below), whose sum is σ = 402229152. Its totient is φ = 402057292.

The previous prime is 402143213. The next prime is 402143281. The reversal of 402143221 is 122341204.

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 a cyclic number.

It is not a de Polignac number, because 402143221 - 2³ = 402143213 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 (402143281) 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, 35515 + ... + 45448.

It is an arithmetic number, because the mean of its divisors is an integer number (100557288).

Almost surely, 2^402143221 is an apocalyptic number.

It is an amenable number.

402143221 is a deficient number, since it is larger than the sum of its proper divisors (85931).

402143221 is an equidigital number, since it uses as much as digits as its factorization.

402143221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85930.

The product of its (nonzero) digits is 384, while the sum is 19.

The square root of 402143221 is about 20053.5089448206. The cubic root of 402143221 is about 738.1199053369.

Adding to 402143221 its reverse (122341204), we get a palindrome (524484425).

The spelling of 402143221 in words is "four hundred two million, one hundred forty-three thousand, two hundred twenty-one".