802421 has 2 divisors, whose sum is σ = 802422. Its totient is φ = 802420.

The previous prime is 802387. The next prime is 802441. The reversal of 802421 is 124208.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 790321 + 12100 = 889^2 + 110^2 .

It is a cyclic number.

It is not a de Polignac number, because 802421 - 2⁶ = 802357 is a prime.

It is a super-2 number, since 2×802421² = 1287758922482, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 802421.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 802421.

It is not a weakly prime, because it can be changed into another prime (802441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 401210 + 401211.

It is an arithmetic number, because the mean of its divisors is an integer number (401211).

2⁸⁰²⁴²¹ is an apocalyptic number.

It is an amenable number.

802421 is a deficient number, since it is larger than the sum of its proper divisors (1).

802421 is an equidigital number, since it uses as much as digits as its factorization.

802421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 17.

The square root of 802421 is about 895.7795487730. The cubic root of 802421 is about 92.9253264220.

Adding to 802421 its reverse (124208), we get a palindrome (926629).

The spelling of 802421 in words is "eight hundred two thousand, four hundred twenty-one".