398172628 has 18 divisors (see below), whose sum is σ = 810566106. Its totient is φ = 170645328.

The previous prime is 398172617. The next prime is 398172629. The reversal of 398172628 is 826271893.

It can be written as a sum of positive squares in only one way, i.e., 396328464 + 1844164 = 19908^2 + 1358^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (398172629) 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 5 ways as a sum of consecutive naturals, for example, 1015551 + ... + 1015942.

Almost surely, 2^398172628 is an apocalyptic number.

It is an amenable number.

398172628 is an abundant number, since it is smaller than the sum of its proper divisors (412393478).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

398172628 is a wasteful number, since it uses less digits than its factorization.

398172628 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2031511 (or 2031502 counting only the distinct ones).

The product of its digits is 290304, while the sum is 46.

The square root of 398172628 is about 19954.2634040949. The cubic root of 398172628 is about 735.6825707599.

The spelling of 398172628 in words is "three hundred ninety-eight million, one hundred seventy-two thousand, six hundred twenty-eight".