398551 has 4 divisors (see below), whose sum is σ = 402192. Its totient is φ = 394912.

The previous prime is 398549. The next prime is 398557. The reversal of 398551 is 155893.

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

It is a cyclic number.

It is not a de Polignac number, because 398551 - 2¹ = 398549 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 (398557) 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, 1651 + ... + 1876.

It is an arithmetic number, because the mean of its divisors is an integer number (100548).

2³⁹⁸⁵⁵¹ is an apocalyptic number.

398551 is a deficient number, since it is larger than the sum of its proper divisors (3641).

398551 is a wasteful number, since it uses less digits than its factorization.

398551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3640.

The product of its digits is 5400, while the sum is 31.

The square root of 398551 is about 631.3089576428. The cubic root of 398551 is about 73.5915529649.

It can be divided in two parts, 398 and 551, that added together give a palindrome (949).

The spelling of 398551 in words is "three hundred ninety-eight thousand, five hundred fifty-one".