15661622550000 has 720 divisors, whose sum is σ = 60856554618720. Its totient is φ = 3456311040000.

The previous prime is 15661622549851. The next prime is 15661622550017. The reversal of 15661622550000 is 5522616651.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 213113262 + ... + 213186738.

It is an arithmetic number, because the mean of its divisors is an integer number (84522992526).

Almost surely, 2^{15661622550000} is an apocalyptic number.

15661622550000 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 15661622550000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30428277309360).

15661622550000 is an abundant number, since it is smaller than the sum of its proper divisors (45194932068720).

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

15661622550000 is an equidigital number, since it uses as much as digits as its factorization.

15661622550000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 73556 (or 73523 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 39.

The spelling of 15661622550000 in words is "fifteen trillion, six hundred sixty-one billion, six hundred twenty-two million, five hundred fifty thousand".