1021012311221 has 8 divisors (see below), whose sum is σ = 1169656111680. Its totient is φ = 873064735488.

The previous prime is 1021012311211. The next prime is 1021012311239. The reversal of 1021012311221 is 1221132101201.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1021012311221 is a prime.

It is a super-2 number, since 2×1021012311221² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1021012311221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021012311211) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 174053036 + ... + 174058901.

It is an arithmetic number, because the mean of its divisors is an integer number (146207013960).

Almost surely, 2^{1021012311221} is an apocalyptic number.

It is an amenable number.

1021012311221 is a deficient number, since it is larger than the sum of its proper divisors (148643800459).

1021012311221 is an equidigital number, since it uses as much as digits as its factorization.

1021012311221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 348112363.

The product of its (nonzero) digits is 48, while the sum is 17.

Adding to 1021012311221 its reverse (1221132101201), we get a palindrome (2242144412422).

The spelling of 1021012311221 in words is "one trillion, twenty-one billion, twelve million, three hundred eleven thousand, two hundred twenty-one".