15520240 has 20 divisors (see below), whose sum is σ = 36084744. Its totient is φ = 6208064.

The previous prime is 15520237. The next prime is 15520247. The reversal of 15520240 is 4202551.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15520247) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 96922 + ... + 97081.

Almost surely, 2^15520240 is an apocalyptic number.

15520240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15520240 is an abundant number, since it is smaller than the sum of its proper divisors (20564504).

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

15520240 is a wasteful number, since it uses less digits than its factorization.

15520240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194016 (or 194010 counting only the distinct ones).

The product of its (nonzero) digits is 400, while the sum is 19.

The square root of 15520240 is about 3939.5735809856. The cubic root of 15520240 is about 249.4400266559.

Adding to 15520240 its reverse (4202551), we get a palindrome (19722791).

The spelling of 15520240 in words is "fifteen million, five hundred twenty thousand, two hundred forty".