13720251 has 8 divisors (see below), whose sum is σ = 18333184. Its totient is φ = 9127080.

The previous prime is 13720247. The next prime is 13720271. The reversal of 13720251 is 15202731.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 13720251 - 2² = 13720247 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13720211) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3235 + ... + 6156.

It is an arithmetic number, because the mean of its divisors is an integer number (2291648).

Almost surely, 2^13720251 is an apocalyptic number.

13720251 is a deficient number, since it is larger than the sum of its proper divisors (4612933).

13720251 is an equidigital number, since it uses as much as digits as its factorization.

13720251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9881.

The product of its (nonzero) digits is 420, while the sum is 21.

The square root of 13720251 is about 3704.0857171507. The cubic root of 13720251 is about 239.3980924033.

Adding to 13720251 its reverse (15202731), we get a palindrome (28922982).

The spelling of 13720251 in words is "thirteen million, seven hundred twenty thousand, two hundred fifty-one".