998921724 has 12 divisors (see below), whose sum is σ = 2330817384. Its totient is φ = 332973904.

The previous prime is 998921723. The next prime is 998921747. The reversal of 998921724 is 427129899.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×998921724² = 1995689221358264352, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (998921723) 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, 41621727 + ... + 41621750.

It is an arithmetic number, because the mean of its divisors is an integer number (194234782).

Almost surely, 2^998921724 is an apocalyptic number.

It is an amenable number.

998921724 is an abundant number, since it is smaller than the sum of its proper divisors (1331895660).

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

998921724 is a wasteful number, since it uses less digits than its factorization.

998921724 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 83243484 (or 83243482 counting only the distinct ones).

The product of its digits is 653184, while the sum is 51.

The square root of 998921724 is about 31605.7229627800. The cubic root of 998921724 is about 999.6404454027.

It can be divided in two parts, 9989 and 21724, that added together give a palindrome (31713).

The spelling of 998921724 in words is "nine hundred ninety-eight million, nine hundred twenty-one thousand, seven hundred twenty-four".