20400352 has 48 divisors (see below), whose sum is σ = 46684512. Its totient is φ = 8593920.

The previous prime is 20400349. The next prime is 20400353. The reversal of 20400352 is 25300402.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20400353) 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, 12918 + ... + 14410.

It is an arithmetic number, because the mean of its divisors is an integer number (972594).

Almost surely, 2^20400352 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20400352, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23342256).

20400352 is an abundant number, since it is smaller than the sum of its proper divisors (26284160).

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

20400352 is a wasteful number, since it uses less digits than its factorization.

20400352 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1571 (or 1563 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 16.

The square root of 20400352 is about 4516.6748831414. The cubic root of 20400352 is about 273.2410131737.

Adding to 20400352 its reverse (25300402), we get a palindrome (45700754).

The spelling of 20400352 in words is "twenty million, four hundred thousand, three hundred fifty-two".