15504055440 has 80 divisors (see below), whose sum is σ = 49085215488. Its totient is φ = 4046445568.

The previous prime is 15504055439. The next prime is 15504055517. The reversal of 15504055440 is 4455040551.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 675957 + ... + 698516.

Almost surely, 2^15504055440 is an apocalyptic number.

15504055440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

15504055440 is an abundant number, since it is smaller than the sum of its proper divisors (33581160048).

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

15504055440 is a wasteful number, since it uses less digits than its factorization.

15504055440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1374536 (or 1374530 counting only the distinct ones).

The product of its (nonzero) digits is 40000, while the sum is 33.

Adding to 15504055440 its reverse (4455040551), we get a palindrome (19959095991).

The spelling of 15504055440 in words is "fifteen billion, five hundred four million, fifty-five thousand, four hundred forty".