20511216160121 has 8 divisors (see below), whose sum is σ = 21012497236584. Its totient is φ = 20009983060480.

The previous prime is 20511216160117. The next prime is 20511216160159. The reversal of 20511216160121 is 12106161211502.

It can be written as a sum of positive squares in 4 ways, for example, as 46124005225 + 20465092154896 = 214765^2 + 4523836^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20511216160121 - 2² = 20511216160117 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20511216162121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11127956 + ... + 12839541.

It is an arithmetic number, because the mean of its divisors is an integer number (2626562154573).

Almost surely, 2^{20511216160121} is an apocalyptic number.

It is an amenable number.

20511216160121 is a deficient number, since it is larger than the sum of its proper divisors (501281076463).

20511216160121 is a wasteful number, since it uses less digits than its factorization.

20511216160121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23988411.

The product of its (nonzero) digits is 1440, while the sum is 29.

Adding to 20511216160121 its reverse (12106161211502), we get a palindrome (32617377371623).

The spelling of 20511216160121 in words is "twenty trillion, five hundred eleven billion, two hundred sixteen million, one hundred sixty thousand, one hundred twenty-one".