20398810 has 16 divisors (see below), whose sum is σ = 38878056. Its totient is φ = 7679488.

The previous prime is 20398787. The next prime is 20398817. The reversal of 20398810 is 1889302.

It can be written as a sum of positive squares in 4 ways, for example, as 14508481 + 5890329 = 3809^2 + 2427^2 .

It is a super-2 number, since 2×20398810² = 832222898832200, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20398817) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 59827 + ... + 60166.

Almost surely, 2^20398810 is an apocalyptic number.

20398810 is a deficient number, since it is larger than the sum of its proper divisors (18479246).

20398810 is a wasteful number, since it uses less digits than its factorization.

20398810 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120017.

The product of its (nonzero) digits is 3456, while the sum is 31.

The square root of 20398810 is about 4516.5041791191. The cubic root of 20398810 is about 273.2341285170.

The spelling of 20398810 in words is "twenty million, three hundred ninety-eight thousand, eight hundred ten".