998977 has 4 divisors (see below), whose sum is σ = 1141696. Its totient is φ = 856260.

The previous prime is 998969. The next prime is 998983. The reversal of 998977 is 779899.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 998977 - 2³ = 998969 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 998977.

It is not an unprimeable number, because it can be changed into a prime (998917) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 71349 + ... + 71362.

It is an arithmetic number, because the mean of its divisors is an integer number (285424).

2⁹⁹⁸⁹⁷⁷ is an apocalyptic number.

It is an amenable number.

998977 is a deficient number, since it is larger than the sum of its proper divisors (142719).

998977 is a wasteful number, since it uses less digits than its factorization.

998977 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 142718.

The product of its digits is 285768, while the sum is 49.

The square root of 998977 is about 999.4883691169. The cubic root of 998977 is about 99.9658883653.

The spelling of 998977 in words is "nine hundred ninety-eight thousand, nine hundred seventy-seven".