1221020210331 has 64 divisors (see below), whose sum is σ = 1833382656000. Its totient is φ = 803081889792.

The previous prime is 1221020210327. The next prime is 1221020210341. The reversal of 1221020210331 is 1330120201221.

1221020210331 is a `hidden beast` number, since 1 + 22 + 102 + 0 + 210 + 331 = 666.

It is not a de Polignac number, because 1221020210331 - 2² = 1221020210327 is a prime.

It is a super-2 number, since 2×1221020210331² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1221020210341) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 791327946 + ... + 791329488.

It is an arithmetic number, because the mean of its divisors is an integer number (28646604000).

Almost surely, 2^{1221020210331} is an apocalyptic number.

1221020210331 is a deficient number, since it is larger than the sum of its proper divisors (612362445669).

1221020210331 is a wasteful number, since it uses less digits than its factorization.

1221020210331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2697 (or 2691 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 1221020210331 its reverse (1330120201221), we get a palindrome (2551140411552).

The spelling of 1221020210331 in words is "one trillion, two hundred twenty-one billion, twenty million, two hundred ten thousand, three hundred thirty-one".