13021857 has 16 divisors (see below), whose sum is σ = 19512000. Its totient is φ = 8582112.

The previous prime is 13021843. The next prime is 13021861. The reversal of 13021857 is 75812031.

13021857 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 13021857 - 2¹⁸ = 12759713 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a self number, because there is not a number n which added to its sum of digits gives 13021857.

It is not an unprimeable number, because it can be changed into a prime (13021357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 307 + ... + 5112.

It is an arithmetic number, because the mean of its divisors is an integer number (1219500).

Almost surely, 2^13021857 is an apocalyptic number.

It is an amenable number.

13021857 is a deficient number, since it is larger than the sum of its proper divisors (6490143).

13021857 is an equidigital number, since it uses as much as digits as its factorization.

13021857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5517 (or 5511 counting only the distinct ones).

The product of its (nonzero) digits is 1680, while the sum is 27.

The square root of 13021857 is about 3608.5810230616. The cubic root of 13021857 is about 235.2651722249.

Adding to 13021857 its reverse (75812031), we get a palindrome (88833888).

The spelling of 13021857 in words is "thirteen million, twenty-one thousand, eight hundred fifty-seven".