21451204721112 has 64 divisors (see below), whose sum is σ = 53879879424000. Its totient is φ = 7116832779264.

The previous prime is 21451204721087. The next prime is 21451204721153. The reversal of 21451204721112 is 21112740215412.

It is a congruent number.

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, 25049064 + ... + 25891272.

It is an arithmetic number, because the mean of its divisors is an integer number (841873116000).

Almost surely, 2^{21451204721112} is an apocalyptic number.

It is an amenable number.

21451204721112 is an abundant number, since it is smaller than the sum of its proper divisors (32428674702888).

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

21451204721112 is a wasteful number, since it uses less digits than its factorization.

21451204721112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 847200 (or 847196 counting only the distinct ones).

The product of its (nonzero) digits is 8960, while the sum is 33.

Adding to 21451204721112 its reverse (21112740215412), we get a palindrome (42563944936524).

The spelling of 21451204721112 in words is "twenty-one trillion, four hundred fifty-one billion, two hundred four million, seven hundred twenty-one thousand, one hundred twelve".