21221010121010 has 64 divisors (see below), whose sum is σ = 45168083550720. Its totient is φ = 7023625889280.

The previous prime is 21221010121007. The next prime is 21221010121019. The reversal of 21221010121010 is 1012101012212.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is not an unprimeable number, because it can be changed into a prime (21221010121019) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10414862 + ... + 12284598.

It is an arithmetic number, because the mean of its divisors is an integer number (705751305480).

Almost surely, 2^{21221010121010} is an apocalyptic number.

21221010121010 is an abundant number, since it is smaller than the sum of its proper divisors (23947073429710).

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

21221010121010 is a wasteful number, since it uses less digits than its factorization.

21221010121010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1875371.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21221010121010 its reverse (1012101012212), we get a palindrome (22233111133222).

The spelling of 21221010121010 in words is "twenty-one trillion, two hundred twenty-one billion, ten million, one hundred twenty-one thousand, ten".