21101231205212 has 24 divisors (see below), whose sum is σ = 37011354541056. Its totient is φ = 10526559565808.

The previous prime is 21101231205179. The next prime is 21101231205233. The reversal of 21101231205212 is 21250213210112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 97534463 + ... + 97750569.

It is an arithmetic number, because the mean of its divisors is an integer number (1542139772544).

Almost surely, 2^{21101231205212} is an apocalyptic number.

It is an amenable number.

21101231205212 is a deficient number, since it is larger than the sum of its proper divisors (15910123335844).

21101231205212 is a wasteful number, since it uses less digits than its factorization.

21101231205212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 271657 (or 271655 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 23.

Adding to 21101231205212 its reverse (21250213210112), we get a palindrome (42351444415324).

The spelling of 21101231205212 in words is "twenty-one trillion, one hundred one billion, two hundred thirty-one million, two hundred five thousand, two hundred twelve".