15478654640 has 80 divisors (see below), whose sum is σ = 37256115456. Its totient is φ = 5974425600.

The previous prime is 15478654621. The next prime is 15478654643. The reversal of 15478654640 is 4645687451.

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

It is not an unprimeable number, because it can be changed into a prime (15478654643) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 866600 + ... + 884280.

Almost surely, 2^15478654640 is an apocalyptic number.

15478654640 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 15478654640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18628057728).

15478654640 is an abundant number, since it is smaller than the sum of its proper divisors (21777460816).

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

15478654640 is a wasteful number, since it uses less digits than its factorization.

15478654640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18078 (or 18072 counting only the distinct ones).

The product of its (nonzero) digits is 3225600, while the sum is 50.

The spelling of 15478654640 in words is "fifteen billion, four hundred seventy-eight million, six hundred fifty-four thousand, six hundred forty".