15221436440 has 48 divisors (see below), whose sum is σ = 39839785200. Its totient is φ = 5218777536.

The previous prime is 15221436437. The next prime is 15221436457. The reversal of 15221436440 is 4463412251.

It is a junction number, because it is equal to n+sod(n) for n = 15221436397 and 15221436406.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 3881060 + ... + 3884979.

It is an arithmetic number, because the mean of its divisors is an integer number (829995525).

Almost surely, 2^15221436440 is an apocalyptic number.

15221436440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15221436440 is an abundant number, since it is smaller than the sum of its proper divisors (24618348760).

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

15221436440 is a wasteful number, since it uses less digits than its factorization.

15221436440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7766064 (or 7766053 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 32.

Adding to 15221436440 its reverse (4463412251), we get a palindrome (19684848691).

The spelling of 15221436440 in words is "fifteen billion, two hundred twenty-one million, four hundred thirty-six thousand, four hundred forty".