998451791 has 4 divisors (see below), whose sum is σ = 998516184. Its totient is φ = 998387400.

The previous prime is 998451757. The next prime is 998451799. The reversal of 998451791 is 197154899.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 998451791 - 2¹⁰ = 998450767 is a prime.

It is a super-2 number, since 2×998451791² = 1993811957902215362, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (998451799) 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, 6836 + ... + 45206.

It is an arithmetic number, because the mean of its divisors is an integer number (249629046).

Almost surely, 2^998451791 is an apocalyptic number.

998451791 is a deficient number, since it is larger than the sum of its proper divisors (64393).

998451791 is a wasteful number, since it uses less digits than its factorization.

998451791 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64392.

The product of its digits is 816480, while the sum is 53.

The square root of 998451791 is about 31598.2877858912. The cubic root of 998451791 is about 999.4836637761.

The spelling of 998451791 in words is "nine hundred ninety-eight million, four hundred fifty-one thousand, seven hundred ninety-one".