15505040 has 20 divisors (see below), whose sum is σ = 36049404. Its totient is φ = 6201984.

The previous prime is 15505031. The next prime is 15505043. The reversal of 15505040 is 4050551.

It can be written as a sum of positive squares in 2 ways, for example, as 8386816 + 7118224 = 2896^2 + 2668^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (15505043) 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 3 ways as a sum of consecutive naturals, for example, 96827 + ... + 96986.

Almost surely, 2^15505040 is an apocalyptic number.

15505040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15505040 is an abundant number, since it is smaller than the sum of its proper divisors (20544364).

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

15505040 is a wasteful number, since it uses less digits than its factorization.

15505040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 193826 (or 193820 counting only the distinct ones).

The product of its (nonzero) digits is 500, while the sum is 20.

The square root of 15505040 is about 3937.6439656221. The cubic root of 15505040 is about 249.3585690060.

Adding to 15505040 its reverse (4050551), we get a palindrome (19555591).

The spelling of 15505040 in words is "fifteen million, five hundred five thousand, forty".