215530214521 has 24 divisors (see below), whose sum is σ = 236259085376. Its totient is φ = 196432024320.

The previous prime is 215530214483. The next prime is 215530214531. The reversal of 215530214521 is 125412035512.

It is not a de Polignac number, because 215530214521 - 2¹³ = 215530206329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (215530214531) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2208460 + ... + 2303986.

Almost surely, 2^215530214521 is an apocalyptic number.

It is an amenable number.

215530214521 is a deficient number, since it is larger than the sum of its proper divisors (20728870855).

215530214521 is a wasteful number, since it uses less digits than its factorization.

215530214521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95809 (or 95792 counting only the distinct ones).

The product of its (nonzero) digits is 12000, while the sum is 31.

The spelling of 215530214521 in words is "two hundred fifteen billion, five hundred thirty million, two hundred fourteen thousand, five hundred twenty-one".