21113031400 has 96 divisors (see below), whose sum is σ = 49727620800. Its totient is φ = 8335872000.

The previous prime is 21113031377. The next prime is 21113031403. The reversal of 21113031400 is 413031112.

It is not an unprimeable number, because it can be changed into a prime (21113031403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4920456 + ... + 4924744.

It is an arithmetic number, because the mean of its divisors is an integer number (517996050).

Almost surely, 2^21113031400 is an apocalyptic number.

21113031400 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 21113031400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24863810400).

21113031400 is an abundant number, since it is smaller than the sum of its proper divisors (28614589400).

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

21113031400 is a wasteful number, since it uses less digits than its factorization.

21113031400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4619 (or 4610 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 21113031400 its reverse (413031112), we get a palindrome (21526062512).

The spelling of 21113031400 in words is "twenty-one billion, one hundred thirteen million, thirty-one thousand, four hundred".