21121002120210 has 64 divisors (see below), whose sum is σ = 50815826578944. Its totient is φ = 5618348640000.

The previous prime is 21121002120193. The next prime is 21121002120247. The reversal of 21121002120210 is 1202120012112.

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 21121002120210.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19224340 + ... + 20293280.

It is an arithmetic number, because the mean of its divisors is an integer number (793997290296).

Almost surely, 2^{21121002120210} is an apocalyptic number.

21121002120210 is an abundant number, since it is smaller than the sum of its proper divisors (29694824458734).

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

21121002120210 is a wasteful number, since it uses less digits than its factorization.

21121002120210 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1070579.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21121002120210 its reverse (1202120012112), we get a palindrome (22323122132322).

The spelling of 21121002120210 in words is "twenty-one trillion, one hundred twenty-one billion, two million, one hundred twenty thousand, two hundred ten".