126840569 has 4 divisors (see below), whose sum is σ = 127618896. Its totient is φ = 126062244.

The previous prime is 126840559. The next prime is 126840589. The reversal of 126840569 is 965048621.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 965048621 = 257 ⋅3755053.

It is a de Polignac number, because none of the positive numbers 2^k-126840569 is a prime.

It is a super-2 number, since 2×126840569² = 32177059888487522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (126840509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 388919 + ... + 389244.

It is an arithmetic number, because the mean of its divisors is an integer number (31904724).

Almost surely, 2^126840569 is an apocalyptic number.

It is an amenable number.

126840569 is a deficient number, since it is larger than the sum of its proper divisors (778327).

126840569 is an equidigital number, since it uses as much as digits as its factorization.

126840569 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 778326.

The product of its (nonzero) digits is 103680, while the sum is 41.

The square root of 126840569 is about 11262.3518414228. The cubic root of 126840569 is about 502.4421444409.

The spelling of 126840569 in words is "one hundred twenty-six million, eight hundred forty thousand, five hundred sixty-nine".