126728405 has 8 divisors (see below), whose sum is σ = 157318200. Its totient is φ = 97886656.

The previous prime is 126728369. The next prime is 126728429. The reversal of 126728405 is 504827621.

It can be written as a sum of positive squares in 4 ways, for example, as 5750404 + 120978001 = 2398^2 + 10999^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 126728405 - 2¹² = 126724309 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 436850 + ... + 437139.

It is an arithmetic number, because the mean of its divisors is an integer number (19664775).

Almost surely, 2^126728405 is an apocalyptic number.

It is an amenable number.

126728405 is a deficient number, since it is larger than the sum of its proper divisors (30589795).

126728405 is an equidigital number, since it uses as much as digits as its factorization.

126728405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 874023.

The product of its (nonzero) digits is 26880, while the sum is 35.

The square root of 126728405 is about 11257.3711407238. The cubic root of 126728405 is about 502.2939990408.

The spelling of 126728405 in words is "one hundred twenty-six million, seven hundred twenty-eight thousand, four hundred five".