12553991 has 4 divisors (see below), whose sum is σ = 12741432. Its totient is φ = 12366552.

The previous prime is 12553943. The next prime is 12553993. The reversal of 12553991 is 19935521.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12553991 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12553993) 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, 93620 + ... + 93753.

It is an arithmetic number, because the mean of its divisors is an integer number (3185358).

Almost surely, 2^12553991 is an apocalyptic number.

12553991 is a deficient number, since it is larger than the sum of its proper divisors (187441).

12553991 is an equidigital number, since it uses as much as digits as its factorization.

12553991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 187440.

The product of its digits is 12150, while the sum is 35.

The square root of 12553991 is about 3543.1611591910. The cubic root of 12553991 is about 232.4131004491.

The spelling of 12553991 in words is "twelve million, five hundred fifty-three thousand, nine hundred ninety-one".