21715071515212 has 24 divisors (see below), whose sum is σ = 39004939814400. Its totient is φ = 10573124720400.

The previous prime is 21715071515191. The next prime is 21715071515213. The reversal of 21715071515212 is 21251517051712.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21715071515213) 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, 290177914 + ... + 290252737.

It is an arithmetic number, because the mean of its divisors is an integer number (1625205825600).

Almost surely, 2^{21715071515212} is an apocalyptic number.

It is an amenable number.

21715071515212 is a deficient number, since it is larger than the sum of its proper divisors (17289868299188).

21715071515212 is a wasteful number, since it uses less digits than its factorization.

21715071515212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 580430901 (or 580430899 counting only the distinct ones).

The product of its (nonzero) digits is 49000, while the sum is 40.

Adding to 21715071515212 its reverse (21251517051712), we get a palindrome (42966588566924).

The spelling of 21715071515212 in words is "twenty-one trillion, seven hundred fifteen billion, seventy-one million, five hundred fifteen thousand, two hundred twelve".