13421257 has 4 divisors (see below), whose sum is σ = 13503760. Its totient is φ = 13338756.

The previous prime is 13421251. The next prime is 13421267. The reversal of 13421257 is 75212431.

It is a happy number.

13421257 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 13421257 - 2⁷ = 13421129 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13421251) 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, 41007 + ... + 41332.

It is an arithmetic number, because the mean of its divisors is an integer number (3375940).

Almost surely, 2^13421257 is an apocalyptic number.

It is an amenable number.

13421257 is a deficient number, since it is larger than the sum of its proper divisors (82503).

13421257 is an equidigital number, since it uses as much as digits as its factorization.

13421257 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82502.

The product of its digits is 1680, while the sum is 25.

The square root of 13421257 is about 3663.5033779157. The cubic root of 13421257 is about 237.6463039463.

Adding to 13421257 its reverse (75212431), we get a palindrome (88633688).

The spelling of 13421257 in words is "thirteen million, four hundred twenty-one thousand, two hundred fifty-seven".