21211112000 has 112 divisors (see below), whose sum is σ = 56570313072. Its totient is φ = 7831756800.

The previous prime is 21211111979. The next prime is 21211112017. The reversal of 21211112000 is 21111212.

It can be written as a sum of positive squares in 8 ways, for example, as 5508014656 + 15703097344 = 74216^2 + 125312^2 .

It is a super-2 number, since 2×21211112000² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2024 + ... + 205976.

It is an arithmetic number, because the mean of its divisors is an integer number (505092081).

Almost surely, 2^21211112000 is an apocalyptic number.

21211112000 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 21211112000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28285156536).

21211112000 is an abundant number, since it is smaller than the sum of its proper divisors (35359201072).

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

21211112000 is a wasteful number, since it uses less digits than its factorization.

21211112000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203993 (or 203973 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 21211112000 its reverse (21111212), we get a palindrome (21232223212).

The spelling of 21211112000 in words is "twenty-one billion, two hundred eleven million, one hundred twelve thousand".