998749609 has 45 divisors (see below), whose sum is σ = 1263351971. Its totient is φ = 788810880.

The previous prime is 998749579. The next prime is 998749639. The reversal of 998749609 is 906947899.

The square root of 998749609 is 31603.

It is a perfect power (a square), and thus also a powerful number.

It is an interprime number because it is at equal distance from previous prime (998749579) and next prime (998749639).

It can be written as a sum of positive squares in 7 ways, for example, as 911738025 + 87011584 = 30195^2 + 9328^2 .

It is not a de Polignac number, because 998749609 - 2¹⁵ = 998716841 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (998749639) by changing a digit.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 58749969 + ... + 58749985.

Almost surely, 2^998749609 is an apocalyptic number.

998749609 is the 31603-rd square number.

998749609 is the 15802-nd centered octagonal number.

It is an amenable number.

998749609 is a deficient number, since it is larger than the sum of its proper divisors (264602362).

998749609 is an equidigital number, since it uses as much as digits as its factorization.

998749609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 108 (or 41 counting only the distinct ones).

The product of its (nonzero) digits is 8817984, while the sum is 61.

The cubic root of 998749609 is about 999.5830291595.

The spelling of 998749609 in words is "nine hundred ninety-eight million, seven hundred forty-nine thousand, six hundred nine".