998638 has 8 divisors (see below), whose sum is σ = 1505088. Its totient is φ = 496944.

The previous prime is 998633. The next prime is 998651. The reversal of 998638 is 836899.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 998594 and 998603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (998633) 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, 606 + ... + 1537.

It is an arithmetic number, because the mean of its divisors is an integer number (188136).

2⁹⁹⁸⁶³⁸ is an apocalyptic number.

998638 is a deficient number, since it is larger than the sum of its proper divisors (506450).

998638 is a wasteful number, since it uses less digits than its factorization.

998638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2378.

The product of its digits is 93312, while the sum is 43.

The square root of 998638 is about 999.3187679615. The cubic root of 998638 is about 99.9545793728.

The spelling of 998638 in words is "nine hundred ninety-eight thousand, six hundred thirty-eight".