13121919 has 10 divisors (see below), whose sum is σ = 19602000. Its totient is φ = 8747892.

The previous prime is 13121887. The next prime is 13121921. The reversal of 13121919 is 91912131.

It is not a de Polignac number, because 13121919 - 2⁵ = 13121887 is a prime.

It is a super-2 number, since 2×13121919² = 344369516485122, which contains 22 as substring.

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

It is a junction number, because it is equal to n+sod(n) for n = 13121892 and 13121901.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13121219) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 80919 + ... + 81080.

It is an arithmetic number, because the mean of its divisors is an integer number (1960200).

Almost surely, 2^13121919 is an apocalyptic number.

13121919 is a deficient number, since it is larger than the sum of its proper divisors (6480081).

13121919 is an equidigital number, since it uses as much as digits as its factorization.

13121919 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162011 (or 162002 counting only the distinct ones).

The product of its digits is 486, while the sum is 27.

The square root of 13121919 is about 3622.4189431925. The cubic root of 13121919 is about 235.8662401553.

The spelling of 13121919 in words is "thirteen million, one hundred twenty-one thousand, nine hundred nineteen".