126561553 has 4 divisors (see below), whose sum is σ = 129254400. Its totient is φ = 123868708.

The previous prime is 126561551. The next prime is 126561569. The reversal of 126561553 is 355165621.

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.

It is a cyclic number.

It is not a de Polignac number, because 126561553 - 2¹ = 126561551 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (126561551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1346353 + ... + 1346446.

It is an arithmetic number, because the mean of its divisors is an integer number (32313600).

Almost surely, 2^126561553 is an apocalyptic number.

It is an amenable number.

126561553 is a deficient number, since it is larger than the sum of its proper divisors (2692847).

126561553 is an equidigital number, since it uses as much as digits as its factorization.

126561553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2692846.

The product of its digits is 27000, while the sum is 34.

The square root of 126561553 is about 11249.9579110324. The cubic root of 126561553 is about 502.0734603057.

The spelling of 126561553 in words is "one hundred twenty-six million, five hundred sixty-one thousand, five hundred fifty-three".