21215632516423 has 8 divisors (see below), whose sum is σ = 22463666178480. Its totient is φ = 19967604996480.

The previous prime is 21215632516417. The next prime is 21215632516447. The reversal of 21215632516423 is 32461523651212.

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-21215632516423 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21215632516423.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21215632516123) 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, 6899988 + ... + 9488998.

It is an arithmetic number, because the mean of its divisors is an integer number (2807958272310).

Almost surely, 2^{21215632516423} is an apocalyptic number.

21215632516423 is a deficient number, since it is larger than the sum of its proper divisors (1248033662057).

21215632516423 is a wasteful number, since it uses less digits than its factorization.

21215632516423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3071057.

The product of its digits is 518400, while the sum is 43.

The spelling of 21215632516423 in words is "twenty-one trillion, two hundred fifteen billion, six hundred thirty-two million, five hundred sixteen thousand, four hundred twenty-three".