13661004 has 48 divisors (see below), whose sum is σ = 37184000. Its totient is φ = 3901968.

The previous prime is 13661003. The next prime is 13661017. The reversal of 13661004 is 40016631.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13661003) 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, 2457 + ... + 5775.

Almost surely, 2^13661004 is an apocalyptic number.

13661004 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 13661004, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18592000).

13661004 is an abundant number, since it is smaller than the sum of its proper divisors (23522996).

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

13661004 is a wasteful number, since it uses less digits than its factorization.

13661004 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3347 (or 3331 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 13661004 is about 3696.0795445986. The cubic root of 13661004 is about 239.0530043561.

Adding to 13661004 its reverse (40016631), we get a palindrome (53677635).

The spelling of 13661004 in words is "thirteen million, six hundred sixty-one thousand, four".