13621140 has 72 divisors (see below), whose sum is σ = 44503368. Its totient is φ = 3352320.

The previous prime is 13621123. The next prime is 13621147. The reversal of 13621140 is 4112631.

It is a happy number.

13621140 is a `hidden beast` number, since 1 + 3 + 621 + 1 + 40 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 1468944 + 12152196 = 1212^2 + 3486^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13621147) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 571 + ... + 5250.

Almost surely, 2^13621140 is an apocalyptic number.

13621140 is a gapful number since it is divisible by the number (10) 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 13621140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22251684).

13621140 is an abundant number, since it is smaller than the sum of its proper divisors (30882228).

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

13621140 is a wasteful number, since it uses less digits than its factorization.

13621140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5849 (or 5844 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

The square root of 13621140 is about 3690.6828636446. The cubic root of 13621140 is about 238.8202519797.

Adding to 13621140 its reverse (4112631), we get a palindrome (17733771).

The spelling of 13621140 in words is "thirteen million, six hundred twenty-one thousand, one hundred forty".