1021121201005 has 4 divisors (see below), whose sum is σ = 1225345441212. Its totient is φ = 816896960800.

The previous prime is 1021121200991. The next prime is 1021121201029. The reversal of 1021121201005 is 5001021211201.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 521857425609 + 499263775396 = 722397^2 + 706586^2 .

It is not a de Polignac number, because 1021121201005 - 2²⁹ = 1020584330093 is a prime.

It is a super-2 number, since 2×1021121201005² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1021121201005.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 102112120096 + ... + 102112120105.

It is an arithmetic number, because the mean of its divisors is an integer number (306336360303).

Almost surely, 2^{1021121201005} is an apocalyptic number.

It is an amenable number.

1021121201005 is a deficient number, since it is larger than the sum of its proper divisors (204224240207).

1021121201005 is an equidigital number, since it uses as much as digits as its factorization.

1021121201005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 204224240206.

The product of its (nonzero) digits is 40, while the sum is 16.

Adding to 1021121201005 its reverse (5001021211201), we get a palindrome (6022142412206).

The spelling of 1021121201005 in words is "one trillion, twenty-one billion, one hundred twenty-one million, two hundred one thousand, five".