15666609504 has 192 divisors, whose sum is σ = 51446707200. Its totient is φ = 4063979520.

The previous prime is 15666609503. The next prime is 15666609529. The reversal of 15666609504 is 40590666651.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15666609503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 518197 + ... + 547595.

It is an arithmetic number, because the mean of its divisors is an integer number (267951600).

Almost surely, 2^15666609504 is an apocalyptic number.

15666609504 is a gapful number since it is divisible by the number (14) 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 15666609504, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25723353600).

15666609504 is an abundant number, since it is smaller than the sum of its proper divisors (35780097696).

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

15666609504 is a wasteful number, since it uses less digits than its factorization.

15666609504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29493 (or 29485 counting only the distinct ones).

The product of its (nonzero) digits is 1166400, while the sum is 48.

The spelling of 15666609504 in words is "fifteen billion, six hundred sixty-six million, six hundred nine thousand, five hundred four".