21500524351121 has 8 divisors (see below), whose sum is σ = 22083201572544. Its totient is φ = 20917930391280.

The previous prime is 21500524351091. The next prime is 21500524351183. The reversal of 21500524351121 is 12115342500512.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21500524351121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21500524351321) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20291765 + ... + 21325026.

It is an arithmetic number, because the mean of its divisors is an integer number (2760400196568).

Almost surely, 2^{21500524351121} is an apocalyptic number.

It is an amenable number.

21500524351121 is a deficient number, since it is larger than the sum of its proper divisors (582677221423).

21500524351121 is a wasteful number, since it uses less digits than its factorization.

21500524351121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41630791.

The product of its (nonzero) digits is 12000, while the sum is 32.

Adding to 21500524351121 its reverse (12115342500512), we get a palindrome (33615866851633).

The spelling of 21500524351121 in words is "twenty-one trillion, five hundred billion, five hundred twenty-four million, three hundred fifty-one thousand, one hundred twenty-one".