126721603 has 2 divisors, whose sum is σ = 126721604. Its totient is φ = 126721602.

The previous prime is 126721601. The next prime is 126721613. The reversal of 126721603 is 306127621.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 126721603 - 2¹ = 126721601 is a prime.

Together with 126721601, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (126721601) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63360801 + 63360802.

It is an arithmetic number, because the mean of its divisors is an integer number (63360802).

Almost surely, 2^126721603 is an apocalyptic number.

126721603 is a deficient number, since it is larger than the sum of its proper divisors (1).

126721603 is an equidigital number, since it uses as much as digits as its factorization.

126721603 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 126721603 is about 11257.0690235070. The cubic root of 126721603 is about 502.2850121976.

The spelling of 126721603 in words is "one hundred twenty-six million, seven hundred twenty-one thousand, six hundred three".