126263993621 has 2 divisors, whose sum is σ = 126263993622. Its totient is φ = 126263993620.

The previous prime is 126263993617. The next prime is 126263993657. The reversal of 126263993621 is 126399362621.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 90850399396 + 35413594225 = 301414^2 + 188185^2 .

It is a cyclic number.

It is not a de Polignac number, because 126263993621 - 2² = 126263993617 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 126263993621.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (126263993671) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63131996810 + 63131996811.

It is an arithmetic number, because the mean of its divisors is an integer number (63131996811).

Almost surely, 2^126263993621 is an apocalyptic number.

It is an amenable number.

126263993621 is a deficient number, since it is larger than the sum of its proper divisors (1).

126263993621 is an equidigital number, since it uses as much as digits as its factorization.

126263993621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1259712, while the sum is 50.

The spelling of 126263993621 in words is "one hundred twenty-six billion, two hundred sixty-three million, nine hundred ninety-three thousand, six hundred twenty-one".