20802810 has 128 divisors (see below), whose sum is σ = 61378560. Its totient is φ = 4409856.

The previous prime is 20802809. The next prime is 20802823. The reversal of 20802810 is 1820802.

20802810 is nontrivially palindromic in base 12.

It is a super-2 number, since 2×20802810² = 865513807792200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 284934 + ... + 285006.

It is an arithmetic number, because the mean of its divisors is an integer number (479520).

Almost surely, 2^20802810 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20802810, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30689280).

20802810 is an abundant number, since it is smaller than the sum of its proper divisors (40575750).

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

20802810 is a wasteful number, since it uses less digits than its factorization.

20802810 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 172.

The product of its (nonzero) digits is 256, while the sum is 21.

The square root of 20802810 is about 4561.0097566219. The cubic root of 20802810 is about 275.0261572915.

It can be divided in two parts, 20802 and 810, that added together give a palindrome (21612).

The spelling of 20802810 in words is "twenty million, eight hundred two thousand, eight hundred ten".