13978105 has 4 divisors (see below), whose sum is σ = 16773732. Its totient is φ = 11182480.

The previous prime is 13978099. The next prime is 13978109. The reversal of 13978105 is 50187931.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2499561 + 11478544 = 1581^2 + 3388^2 .

It is not a de Polignac number, because 13978105 - 2¹³ = 13969913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13978109) 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, 1397806 + ... + 1397815.

It is an arithmetic number, because the mean of its divisors is an integer number (4193433).

Almost surely, 2^13978105 is an apocalyptic number.

It is an amenable number.

13978105 is a deficient number, since it is larger than the sum of its proper divisors (2795627).

13978105 is an equidigital number, since it uses as much as digits as its factorization.

13978105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2795626.

The product of its (nonzero) digits is 7560, while the sum is 34.

The square root of 13978105 is about 3738.7303994806. The cubic root of 13978105 is about 240.8885178501. Note that the first 3 decimals are identical.

The spelling of 13978105 in words is "thirteen million, nine hundred seventy-eight thousand, one hundred five".