398621 has 2 divisors, whose sum is σ = 398622. Its totient is φ = 398620.

The previous prime is 398611. The next prime is 398627. The reversal of 398621 is 126893.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 343396 + 55225 = 586^2 + 235^2 .

It is a cyclic number.

It is not a de Polignac number, because 398621 - 2⁶ = 398557 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (398627) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199310 + 199311.

It is an arithmetic number, because the mean of its divisors is an integer number (199311).

2³⁹⁸⁶²¹ is an apocalyptic number.

It is an amenable number.

398621 is a deficient number, since it is larger than the sum of its proper divisors (1).

398621 is an equidigital number, since it uses as much as digits as its factorization.

398621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2592, while the sum is 29.

The square root of 398621 is about 631.3643955752. The cubic root of 398621 is about 73.5958611606.

The spelling of 398621 in words is "three hundred ninety-eight thousand, six hundred twenty-one".