998601905 has 64 divisors (see below), whose sum is σ = 1480066560. Its totient is φ = 631701504.

The previous prime is 998601881. The next prime is 998601907. The reversal of 998601905 is 509106899.

It is not a de Polignac number, because 998601905 - 2⁶ = 998601841 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 998601905.

It is not an unprimeable number, because it can be changed into a prime (998601907) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 7288997 + ... + 7289133.

It is an arithmetic number, because the mean of its divisors is an integer number (23126040).

Almost surely, 2^998601905 is an apocalyptic number.

998601905 is a gapful number since it is divisible by the number (95) formed by its first and last digit.

998601905 is the 25802-nd pentagonal number.

It is an amenable number.

998601905 is a deficient number, since it is larger than the sum of its proper divisors (481464655).

998601905 is a wasteful number, since it uses less digits than its factorization.

998601905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 378.

The product of its (nonzero) digits is 174960, while the sum is 47.

The square root of 998601905 is about 31600.6630468413. The cubic root of 998601905 is about 999.5337509790.

The spelling of 998601905 in words is "nine hundred ninety-eight million, six hundred one thousand, nine hundred five".