21120001210100 has 72 divisors (see below), whose sum is σ = 49562328641280. Its totient is φ = 7765525918080.

The previous prime is 21120001210081. The next prime is 21120001210109. The reversal of 21120001210100 is 101210002112.

It is a super-2 number, since 2×21120001210100² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21120001210109) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 33677072 + ... + 34298471.

Almost surely, 2^{21120001210100} is an apocalyptic number.

21120001210100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21120001210100 is an abundant number, since it is smaller than the sum of its proper divisors (28442327431180).

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

21120001210100 is a wasteful number, since it uses less digits than its factorization.

21120001210100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67975809 (or 67975802 counting only the distinct ones).

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

Adding to 21120001210100 its reverse (101210002112), we get a palindrome (21221211212212).

The spelling of 21120001210100 in words is "twenty-one trillion, one hundred twenty billion, one million, two hundred ten thousand, one hundred".