13778424 has 80 divisors (see below), whose sum is σ = 42122520. Its totient is φ = 4173120.

The previous prime is 13778423. The next prime is 13778437. The reversal of 13778424 is 42487731.

It is a happy number.

It is a Smith number, since the sum of its digits (36) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13778423) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 6162 + ... + 8094.

Almost surely, 2^13778424 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 13778424, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21061260).

13778424 is an abundant number, since it is smaller than the sum of its proper divisors (28344096).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

13778424 is a wasteful number, since it uses less digits than its factorization.

13778424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1962 (or 1949 counting only the distinct ones).

The product of its digits is 37632, while the sum is 36.

The square root of 13778424 is about 3711.9299562357. The cubic root of 13778424 is about 239.7359596177.

It can be divided in two parts, 1377 and 8424, that added together give a square (9801 = 99²).

The spelling of 13778424 in words is "thirteen million, seven hundred seventy-eight thousand, four hundred twenty-four".