1021013123261 has 2 divisors, whose sum is σ = 1021013123262. Its totient is φ = 1021013123260.

The previous prime is 1021013123131. The next prime is 1021013123357. The reversal of 1021013123261 is 1623213101201.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1019282064025 + 1731059236 = 1009595^2 + 41606^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021013123261 - 2¹⁰ = 1021013122237 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1021013120261) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510506561630 + 510506561631.

It is an arithmetic number, because the mean of its divisors is an integer number (510506561631).

Almost surely, 2^{1021013123261} is an apocalyptic number.

It is an amenable number.

1021013123261 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021013123261 is an equidigital number, since it uses as much as digits as its factorization.

1021013123261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 432, while the sum is 23.

Adding to 1021013123261 its reverse (1623213101201), we get a palindrome (2644226224462).

The spelling of 1021013123261 in words is "one trillion, twenty-one billion, thirteen million, one hundred twenty-three thousand, two hundred sixty-one".