13643971 has 4 divisors (see below), whose sum is σ = 14884344. Its totient is φ = 12403600.

The previous prime is 13643963. The next prime is 13643977. The reversal of 13643971 is 17934631.

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

It is not a de Polignac number, because 13643971 - 2³ = 13643963 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13643977) 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, 620170 + ... + 620191.

It is an arithmetic number, because the mean of its divisors is an integer number (3721086).

Almost surely, 2^13643971 is an apocalyptic number.

13643971 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

13643971 is a deficient number, since it is larger than the sum of its proper divisors (1240373).

13643971 is a wasteful number, since it uses less digits than its factorization.

13643971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1240372.

The product of its digits is 13608, while the sum is 34.

The square root of 13643971 is about 3693.7746276675. The cubic root of 13643971 is about 238.9536099221.

It can be divided in two parts, 1364 and 3971, that added together give a palindrome (5335).

The spelling of 13643971 in words is "thirteen million, six hundred forty-three thousand, nine hundred seventy-one".