21012012211110 has 256 divisors, whose sum is σ = 53175632412672. Its totient is φ = 5307642547200.

The previous prime is 21012012211103. The next prime is 21012012211129. The reversal of 21012012211110 is 1111221021012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21012012211110.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 7496256969 + ... + 7496259771.

It is an arithmetic number, because the mean of its divisors is an integer number (207717314112).

Almost surely, 2^{21012012211110} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21012012211110, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26587816206336).

21012012211110 is an abundant number, since it is smaller than the sum of its proper divisors (32163620201562).

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

21012012211110 is a wasteful number, since it uses less digits than its factorization.

21012012211110 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3691.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21012012211110 its reverse (1111221021012), we get a palindrome (22123233232122).

The spelling of 21012012211110 in words is "twenty-one trillion, twelve billion, twelve million, two hundred eleven thousand, one hundred ten".