1021121212021 has 4 divisors (see below), whose sum is σ = 1021782990112. Its totient is φ = 1020459433932.

The previous prime is 1021121211991. The next prime is 1021121212043. The reversal of 1021121212021 is 1202121211201.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 1021121212021 - 2⁵ = 1021121211989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1021121211986 and 1021121212004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1021121212081) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 330886731 + ... + 330889816.

It is an arithmetic number, because the mean of its divisors is an integer number (255445747528).

Almost surely, 2^{1021121212021} is an apocalyptic number.

It is an amenable number.

1021121212021 is a deficient number, since it is larger than the sum of its proper divisors (661778091).

1021121212021 is an equidigital number, since it uses as much as digits as its factorization.

1021121212021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 661778090.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 1021121212021 its reverse (1202121211201), we get a palindrome (2223242423222).

The spelling of 1021121212021 in words is "one trillion, twenty-one billion, one hundred twenty-one million, two hundred twelve thousand, twenty-one".