126729561 has 8 divisors (see below), whose sum is σ = 193111744. Its totient is φ = 72416880.

The previous prime is 126729541. The next prime is 126729571. The reversal of 126729561 is 165927621.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 126729561 - 2⁵ = 126729529 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (126729541) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3017350 + ... + 3017391.

It is an arithmetic number, because the mean of its divisors is an integer number (24138968).

Almost surely, 2^126729561 is an apocalyptic number.

It is an amenable number.

126729561 is a deficient number, since it is larger than the sum of its proper divisors (66382183).

126729561 is an equidigital number, since it uses as much as digits as its factorization.

126729561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6034751.

The product of its digits is 45360, while the sum is 39.

The square root of 126729561 is about 11257.4224847431. The cubic root of 126729561 is about 502.2955263229.

The spelling of 126729561 in words is "one hundred twenty-six million, seven hundred twenty-nine thousand, five hundred sixty-one".