2102131261 has 2 divisors, whose sum is σ = 2102131262. Its totient is φ = 2102131260.

The previous prime is 2102131211. The next prime is 2102131267. The reversal of 2102131261 is 1621312012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2101764025 + 367236 = 45845^2 + 606^2 .

It is a cyclic number.

It is not a de Polignac number, because 2102131261 - 2⁹ = 2102130749 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2102131267) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1051065630 + 1051065631.

It is an arithmetic number, because the mean of its divisors is an integer number (1051065631).

Almost surely, 2^2102131261 is an apocalyptic number.

It is an amenable number.

2102131261 is a deficient number, since it is larger than the sum of its proper divisors (1).

2102131261 is an equidigital number, since it uses as much as digits as its factorization.

2102131261 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 2102131261 is about 45849.0050164668. The cubic root of 2102131261 is about 1281.0122325525.

Adding to 2102131261 its reverse (1621312012), we get a palindrome (3723443273).

The spelling of 2102131261 in words is "two billion, one hundred two million, one hundred thirty-one thousand, two hundred sixty-one".