20151232400 has 120 divisors (see below), whose sum is σ = 52190487720. Its totient is φ = 7432888320.

The previous prime is 20151232327. The next prime is 20151232441. The reversal of 20151232400 is 423215102.

It can be written as a sum of positive squares in 12 ways, for example, as 17900299264 + 2250933136 = 133792^2 + 47444^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9738566 + ... + 9740634.

It is an arithmetic number, because the mean of its divisors is an integer number (434920731).

Almost surely, 2^20151232400 is an apocalyptic number.

20151232400 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 20151232400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26095243860).

20151232400 is an abundant number, since it is smaller than the sum of its proper divisors (32039255320).

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

20151232400 is a wasteful number, since it uses less digits than its factorization.

20151232400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3973 (or 3962 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

Adding to 20151232400 its reverse (423215102), we get a palindrome (20574447502).

The spelling of 20151232400 in words is "twenty billion, one hundred fifty-one million, two hundred thirty-two thousand, four hundred".