13217257447 has 4 divisors (see below), whose sum is σ = 13298345080. Its totient is φ = 13136169816.

The previous prime is 13217257429. The next prime is 13217257457. The reversal of 13217257447 is 74475271231.

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-13217257447 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 (13217257457) 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, 40543572 + ... + 40543897.

It is an arithmetic number, because the mean of its divisors is an integer number (3324586270).

Almost surely, 2^13217257447 is an apocalyptic number.

13217257447 is a deficient number, since it is larger than the sum of its proper divisors (81087633).

13217257447 is an equidigital number, since it uses as much as digits as its factorization.

13217257447 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81087632.

The product of its digits is 329280, while the sum is 43.

The spelling of 13217257447 in words is "thirteen billion, two hundred seventeen million, two hundred fifty-seven thousand, four hundred forty-seven".