1210121011021 has 8 divisors (see below), whose sum is σ = 1324571296664. Its totient is φ = 1098722733120.

The previous prime is 1210121011007. The next prime is 1210121011031. The reversal of 1210121011021 is 1201101210121.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 80128624900 + 1129992386121 = 283070^2 + 1063011^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 1210121011021 - 2¹⁹ = 1210120486733 is a prime.

It is a super-2 number, since 2×1210121011021² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1210121010992 and 1210121011010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1210121011031) 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, 763001106 + ... + 763002691.

It is an arithmetic number, because the mean of its divisors is an integer number (165571412083).

Almost surely, 2^{1210121011021} is an apocalyptic number.

It is an amenable number.

1210121011021 is a deficient number, since it is larger than the sum of its proper divisors (114450285643).

1210121011021 is a wasteful number, since it uses less digits than its factorization.

1210121011021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1526003871.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 1210121011021 its reverse (1201101210121), we get a palindrome (2411222221142).

The spelling of 1210121011021 in words is "one trillion, two hundred ten billion, one hundred twenty-one million, eleven thousand, twenty-one".