15565332420 has 144 divisors (see below), whose sum is σ = 52899432768. Its totient is φ = 3671412480.

The previous prime is 15565332403. The next prime is 15565332439. The reversal of 15565332420 is 2423356551.

15565332420 is a `hidden beast` number, since 1 + 556 + 53 + 32 + 4 + 20 = 666.

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

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 32974 + ... + 179493.

It is an arithmetic number, because the mean of its divisors is an integer number (367357172).

Almost surely, 2^15565332420 is an apocalyptic number.

15565332420 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 15565332420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26449716384).

15565332420 is an abundant number, since it is smaller than the sum of its proper divisors (37334100348).

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

15565332420 is a wasteful number, since it uses less digits than its factorization.

15565332420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 212530 (or 212525 counting only the distinct ones).

The product of its (nonzero) digits is 108000, while the sum is 36.

Adding to 15565332420 its reverse (2423356551), we get a palindrome (17988688971).

The spelling of 15565332420 in words is "fifteen billion, five hundred sixty-five million, three hundred thirty-two thousand, four hundred twenty".