20998774 has 16 divisors (see below), whose sum is σ = 33440688. Its totient is φ = 9855232.

The previous prime is 20998771. The next prime is 20998777. The reversal of 20998774 is 47789902.

It is an interprime number because it is at equal distance from previous prime (20998771) and next prime (20998777).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20998771) 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 7 ways as a sum of consecutive naturals, for example, 18594 + ... + 19690.

It is an arithmetic number, because the mean of its divisors is an integer number (2090043).

Almost surely, 2^20998774 is an apocalyptic number.

20998774 is a deficient number, since it is larger than the sum of its proper divisors (12441914).

20998774 is a wasteful number, since it uses less digits than its factorization.

20998774 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1679.

The product of its (nonzero) digits is 254016, while the sum is 46.

The square root of 20998774 is about 4582.4419254367. The cubic root of 20998774 is about 275.8870485796.

The spelling of 20998774 in words is "twenty million, nine hundred ninety-eight thousand, seven hundred seventy-four".