3121103561 has 2 divisors, whose sum is σ = 3121103562. Its totient is φ = 3121103560.

The previous prime is 3121103551. The next prime is 3121103563. The reversal of 3121103561 is 1653011213.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2447181961 + 673921600 = 49469^2 + 25960^2 .

It is a cyclic number.

It is not a de Polignac number, because 3121103561 - 2⁶ = 3121103497 is a prime.

Together with 3121103563, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (3121103563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1560551780 + 1560551781.

It is an arithmetic number, because the mean of its divisors is an integer number (1560551781).

Almost surely, 2^3121103561 is an apocalyptic number.

It is an amenable number.

3121103561 is a deficient number, since it is larger than the sum of its proper divisors (1).

3121103561 is an equidigital number, since it uses as much as digits as its factorization.

3121103561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 3121103561 is about 55866.8377572957. The cubic root of 3121103561 is about 1461.4009760237.

Adding to 3121103561 its reverse (1653011213), we get a palindrome (4774114774).

The spelling of 3121103561 in words is "three billion, one hundred twenty-one million, one hundred three thousand, five hundred sixty-one".