21155003452212 has 96 divisors (see below), whose sum is σ = 56781610905600. Its totient is φ = 6004892610432.

The previous prime is 21155003452139. The next prime is 21155003452381. The reversal of 21155003452212 is 21225430055112.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 15415413 + ... + 16731555.

It is an arithmetic number, because the mean of its divisors is an integer number (591475113600).

Almost surely, 2^{21155003452212} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21155003452212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28390805452800).

21155003452212 is an abundant number, since it is smaller than the sum of its proper divisors (35626607453388).

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

21155003452212 is a wasteful number, since it uses less digits than its factorization.

21155003452212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1317405 (or 1317403 counting only the distinct ones).

The product of its (nonzero) digits is 24000, while the sum is 33.

The spelling of 21155003452212 in words is "twenty-one trillion, one hundred fifty-five billion, three million, four hundred fifty-two thousand, two hundred twelve".