21200111004 has 48 divisors (see below), whose sum is σ = 52090980480. Its totient is φ = 6692132160.

The previous prime is 21200111003. The next prime is 21200111017. The reversal of 21200111004 is 40011100212.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21200111003) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 607987 + ... + 641909.

It is an arithmetic number, because the mean of its divisors is an integer number (1085228760).

Almost surely, 2^21200111004 is an apocalyptic number.

It is an amenable number.

21200111004 is an abundant number, since it is smaller than the sum of its proper divisors (30890869476).

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

21200111004 is a wasteful number, since it uses less digits than its factorization.

21200111004 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36690 (or 36688 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21200111004 its reverse (40011100212), we get a palindrome (61211211216).

The spelling of 21200111004 in words is "twenty-one billion, two hundred million, one hundred eleven thousand, four".