126856919261 has 2 divisors, whose sum is σ = 126856919262. Its totient is φ = 126856919260.

The previous prime is 126856919251. The next prime is 126856919263. The reversal of 126856919261 is 162919658621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 72983724025 + 53873195236 = 270155^2 + 232106^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-126856919261 is a prime.

It is a super-2 number, since 2×126856919261² (a number of 23 digits) contains 22 as substring.

Together with 126856919263, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 126856919197 and 126856919206.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (126856919263) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63428459630 + 63428459631.

It is an arithmetic number, because the mean of its divisors is an integer number (63428459631).

Almost surely, 2^126856919261 is an apocalyptic number.

It is an amenable number.

126856919261 is a deficient number, since it is larger than the sum of its proper divisors (1).

126856919261 is an equidigital number, since it uses as much as digits as its factorization.

126856919261 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2799360, while the sum is 56.

The spelling of 126856919261 in words is "one hundred twenty-six billion, eight hundred fifty-six million, nine hundred nineteen thousand, two hundred sixty-one".