20406100 has 72 divisors (see below), whose sum is σ = 52059168. Its totient is φ = 6844800.

The previous prime is 20406017. The next prime is 20406107. The reversal of 20406100 is 160402.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20406107) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13587 + ... + 15013.

It is an arithmetic number, because the mean of its divisors is an integer number (723044).

Almost surely, 2^20406100 is an apocalyptic number.

20406100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20406100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26029584).

20406100 is an abundant number, since it is smaller than the sum of its proper divisors (31653068).

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

20406100 is a wasteful number, since it uses less digits than its factorization.

20406100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1465 (or 1458 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 20406100 is about 4517.3111471317. The cubic root of 20406100 is about 273.2666735456.

Adding to 20406100 its reverse (160402), we get a palindrome (20566502).

The spelling of 20406100 in words is "twenty million, four hundred six thousand, one hundred".