10001120400 has 180 divisors, whose sum is σ = 36748459332. Its totient is φ = 2510069760.

The previous prime is 10001120341. The next prime is 10001120401. The reversal of 10001120400 is 402110001.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 169208064 + 9831912336 = 13008^2 + 99156^2 .

It is a tau number, because it is divible by the number of its divisors (180).

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10001120401) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 20509 + ... + 142908.

Almost surely, 2^10001120400 is an apocalyptic number.

10001120400 is a gapful number since it is divisible by the number (10) 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 10001120400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18374229666).

10001120400 is an abundant number, since it is smaller than the sum of its proper divisors (26747338932).

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

10001120400 is a wasteful number, since it uses less digits than its factorization.

10001120400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 163458 (or 163444 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

Adding to 10001120400 its reverse (402110001), we get a palindrome (10403230401).

The spelling of 10001120400 in words is "ten billion, one million, one hundred twenty thousand, four hundred".