121221021222021 has 32 divisors (see below), whose sum is σ = 193522299854848. Its totient is φ = 66034148685120.

The previous prime is 121221021221981. The next prime is 121221021222073. The reversal of 121221021222021 is 120222120122121.

It is not a de Polignac number, because 121221021222021 - 2²⁷ = 121220887004293 is a prime.

It is a super-2 number, since 2×121221021222021² (a number of 29 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221021222421) 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, 1389563890 + ... + 1389651123.

It is an arithmetic number, because the mean of its divisors is an integer number (6047571870464).

Almost surely, 2^{121221021222021} is an apocalyptic number.

It is an amenable number.

121221021222021 is a deficient number, since it is larger than the sum of its proper divisors (72301278632827).

121221021222021 is a wasteful number, since it uses less digits than its factorization.

121221021222021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2779215121.

The product of its (nonzero) digits is 256, while the sum is 21.

Adding to 121221021222021 its reverse (120222120122121), we get a palindrome (241443141344142).

The spelling of 121221021222021 in words is "one hundred twenty-one trillion, two hundred twenty-one billion, twenty-one million, two hundred twenty-two thousand, twenty-one".