20019810 has 32 divisors (see below), whose sum is σ = 48408192. Its totient is φ = 5298560.

The previous prime is 20019781. The next prime is 20019817. The reversal of 20019810 is 1891002.

It is a super-2 number, since 2×20019810² = 801585584872200, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (20019817) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1675 + ... + 6545.

It is an arithmetic number, because the mean of its divisors is an integer number (1512756).

Almost surely, 2^20019810 is an apocalyptic number.

20019810 is an abundant number, since it is smaller than the sum of its proper divisors (28388382).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20019810 is a wasteful number, since it uses less digits than its factorization.

20019810 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5018.

The product of its (nonzero) digits is 144, while the sum is 21.

The square root of 20019810 is about 4474.3502321566. The cubic root of 20019810 is about 271.5313531075.

It can be divided in two parts, 2001 and 9810, that added together give a palindrome (11811).

The spelling of 20019810 in words is "twenty million, nineteen thousand, eight hundred ten".