13781409 has 8 divisors (see below), whose sum is σ = 19008960. Its totient is φ = 8870736.

The previous prime is 13781401. The next prime is 13781413. The reversal of 13781409 is 90418731.

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

It is not a de Polignac number, because 13781409 - 2³ = 13781401 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 13781409.

It is not an unprimeable number, because it can be changed into a prime (13781401) 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, 79117 + ... + 79290.

It is an arithmetic number, because the mean of its divisors is an integer number (2376120).

Almost surely, 2^13781409 is an apocalyptic number.

It is an amenable number.

13781409 is a deficient number, since it is larger than the sum of its proper divisors (5227551).

13781409 is a wasteful number, since it uses less digits than its factorization.

13781409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 158439.

The product of its (nonzero) digits is 6048, while the sum is 33.

The square root of 13781409 is about 3712.3320164016. The cubic root of 13781409 is about 239.7532707453.

The spelling of 13781409 in words is "thirteen million, seven hundred eighty-one thousand, four hundred nine".