15661222560 has 384 divisors, whose sum is σ = 57607925760. Its totient is φ = 3966133248.

The previous prime is 15661222523. The next prime is 15661222561. The reversal of 15661222560 is 6522216651.

15661222560 is a `hidden beast` number, since 1 + 5 + 66 + 12 + 22 + 560 = 666.

15661222560 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (15661222561) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 16195197 + ... + 16196163.

It is an arithmetic number, because the mean of its divisors is an integer number (150020640).

Almost surely, 2^15661222560 is an apocalyptic number.

15661222560 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 15661222560, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28803962880).

15661222560 is an abundant number, since it is smaller than the sum of its proper divisors (41946703200).

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

15661222560 is a wasteful number, since it uses less digits than its factorization.

15661222560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1177 (or 1163 counting only the distinct ones).

The product of its (nonzero) digits is 43200, while the sum is 36.

The spelling of 15661222560 in words is "fifteen billion, six hundred sixty-one million, two hundred twenty-two thousand, five hundred sixty".