21516151120416 has 144 divisors (see below), whose sum is σ = 61823067808320. Its totient is φ = 7097536535040.

The previous prime is 21516151120351. The next prime is 21516151120447. The reversal of 21516151120416 is 61402115161512.

21516151120416 is a `hidden beast` number, since 2 + 1 + 5 + 1 + 615 + 1 + 1 + 20 + 4 + 16 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

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 23 ways as a sum of consecutive naturals, for example, 43031206 + ... + 43528346.

It is an arithmetic number, because the mean of its divisors is an integer number (429326859780).

Almost surely, 2^{21516151120416} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21516151120416, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30911533904160).

21516151120416 is an abundant number, since it is smaller than the sum of its proper divisors (40306916687904).

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

21516151120416 is a wasteful number, since it uses less digits than its factorization.

21516151120416 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 498719 (or 498708 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 36.

Adding to 21516151120416 its reverse (61402115161512), we get a palindrome (82918266281928).

The spelling of 21516151120416 in words is "twenty-one trillion, five hundred sixteen billion, one hundred fifty-one million, one hundred twenty thousand, four hundred sixteen".