398212421 has 4 divisors (see below), whose sum is σ = 398399532. Its totient is φ = 398025312.

The previous prime is 398212387. The next prime is 398212429. The reversal of 398212421 is 124212893.

398212421 = 14110² + 14111².

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 199092100 + 199120321 = 14110^2 + 14111^2 .

It is a cyclic number.

It is not a de Polignac number, because 398212421 - 2⁶ = 398212357 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 (398212429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 90326 + ... + 94631.

It is an arithmetic number, because the mean of its divisors is an integer number (99599883).

Almost surely, 2^398212421 is an apocalyptic number.

398212421 is the 14111-st centered square number.

It is an amenable number.

398212421 is a deficient number, since it is larger than the sum of its proper divisors (187111).

398212421 is a wasteful number, since it uses less digits than its factorization.

398212421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187110.

The product of its digits is 6912, while the sum is 32.

The square root of 398212421 is about 19955.2604843936. The cubic root of 398212421 is about 735.7070777528.

The spelling of 398212421 in words is "three hundred ninety-eight million, two hundred twelve thousand, four hundred twenty-one".