1100021120981 has 2 divisors, whose sum is σ = 1100021120982. Its totient is φ = 1100021120980.

The previous prime is 1100021120977. The next prime is 1100021121103. The reversal of 1100021120981 is 1890211200011.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 718029137956 + 381991983025 = 847366^2 + 618055^2 .

It is an emirp because it is prime and its reverse (1890211200011) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1100021120981 - 2² = 1100021120977 is a prime.

It is a super-2 number, since 2×1100021120981² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1100021120981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1100021150981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 550010560490 + 550010560491.

It is an arithmetic number, because the mean of its divisors is an integer number (550010560491).

Almost surely, 2^{1100021120981} is an apocalyptic number.

It is an amenable number.

1100021120981 is a deficient number, since it is larger than the sum of its proper divisors (1).

1100021120981 is an equidigital number, since it uses as much as digits as its factorization.

1100021120981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 288, while the sum is 26.

Adding to 1100021120981 its reverse (1890211200011), we get a palindrome (2990232320992).

The spelling of 1100021120981 in words is "one trillion, one hundred billion, twenty-one million, one hundred twenty thousand, nine hundred eighty-one".