101220101261 has 2 divisors, whose sum is σ = 101220101262. Its totient is φ = 101220101260.

The previous prime is 101220101233. The next prime is 101220101293. The reversal of 101220101261 is 162101022101.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 97900152100 + 3319949161 = 312890^2 + 57619^2 .

It is a cyclic number.

It is not a de Polignac number, because 101220101261 - 2¹⁰ = 101220100237 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (101220101201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50610050630 + 50610050631.

It is an arithmetic number, because the mean of its divisors is an integer number (50610050631).

Almost surely, 2^101220101261 is an apocalyptic number.

It is an amenable number.

101220101261 is a deficient number, since it is larger than the sum of its proper divisors (1).

101220101261 is an equidigital number, since it uses as much as digits as its factorization.

101220101261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 17.

Adding to 101220101261 its reverse (162101022101), we get a palindrome (263321123362).

The spelling of 101220101261 in words is "one hundred one billion, two hundred twenty million, one hundred one thousand, two hundred sixty-one".