126001609 has 4 divisors (see below), whose sum is σ = 126730116. Its totient is φ = 125273104.

The previous prime is 126001591. The next prime is 126001621. The reversal of 126001609 is 906100621.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 67815225 + 58186384 = 8235^2 + 7628^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-126001609 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (126001669) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 363994 + ... + 364339.

It is an arithmetic number, because the mean of its divisors is an integer number (31682529).

Almost surely, 2^126001609 is an apocalyptic number.

It is an amenable number.

126001609 is a deficient number, since it is larger than the sum of its proper divisors (728507).

126001609 is an equidigital number, since it uses as much as digits as its factorization.

126001609 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 728506.

The product of its (nonzero) digits is 648, while the sum is 25.

The square root of 126001609 is about 11225.0438306494. The cubic root of 126001609 is about 501.3319274547.

The spelling of 126001609 in words is "one hundred twenty-six million, one thousand, six hundred nine".