126786721 has 2 divisors, whose sum is σ = 126786722. Its totient is φ = 126786720.

The previous prime is 126786691. The next prime is 126786727. The reversal of 126786721 is 127687621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 115863696 + 10923025 = 10764^2 + 3305^2 .

It is a cyclic number.

It is not a de Polignac number, because 126786721 - 2⁵ = 126786689 is a prime.

It is not a weakly prime, because it can be changed into another prime (126786727) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63393360 + 63393361.

It is an arithmetic number, because the mean of its divisors is an integer number (63393361).

Almost surely, 2^126786721 is an apocalyptic number.

It is an amenable number.

126786721 is a deficient number, since it is larger than the sum of its proper divisors (1).

126786721 is an equidigital number, since it uses as much as digits as its factorization.

126786721 is an evil number, because the sum of its binary digits is even.

The product of its digits is 56448, while the sum is 40.

The square root of 126786721 is about 11259.9609679608. The cubic root of 126786721 is about 502.3710332963.

The spelling of 126786721 in words is "one hundred twenty-six million, seven hundred eighty-six thousand, seven hundred twenty-one".