13206640 has 20 divisors (see below), whose sum is σ = 30705624. Its totient is φ = 5282624.

The previous prime is 13206631. The next prime is 13206679. The reversal of 13206640 is 4660231.

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 82462 + ... + 82621.

Almost surely, 2^13206640 is an apocalyptic number.

13206640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

13206640 is an abundant number, since it is smaller than the sum of its proper divisors (17498984).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

13206640 is a wasteful number, since it uses less digits than its factorization.

13206640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165096 (or 165090 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 13206640 is about 3634.0941099537. The cubic root of 13206640 is about 236.3727710294.

Adding to 13206640 its reverse (4660231), we get a palindrome (17866871).

The spelling of 13206640 in words is "thirteen million, two hundred six thousand, six hundred forty".