21100400412 has 48 divisors (see below), whose sum is σ = 60596024832. Its totient is φ = 5564940480.

The previous prime is 21100400411. The next prime is 21100400423. The reversal of 21100400412 is 21400400112.

It is a junction number, because it is equal to n+sod(n) for n = 21100400391 and 21100400400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21100400411) 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 15 ways as a sum of consecutive naturals, for example, 9660264 + ... + 9662447.

It is an arithmetic number, because the mean of its divisors is an integer number (1262417184).

Almost surely, 2^21100400412 is an apocalyptic number.

It is an amenable number.

21100400412 is an abundant number, since it is smaller than the sum of its proper divisors (39495624420).

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

21100400412 is a wasteful number, since it uses less digits than its factorization.

21100400412 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19322738 (or 19322736 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21100400412 its reverse (21400400112), we get a palindrome (42500800524).

The spelling of 21100400412 in words is "twenty-one billion, one hundred million, four hundred thousand, four hundred twelve".