216530562621 has 4 divisors (see below), whose sum is σ = 288707416832. Its totient is φ = 144353708412.

The previous prime is 216530562617. The next prime is 216530562637. The reversal of 216530562621 is 126265035612.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 216530562621 - 2² = 216530562617 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 216530562621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216530566621) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 36088427101 + ... + 36088427106.

It is an arithmetic number, because the mean of its divisors is an integer number (72176854208).

Almost surely, 2^216530562621 is an apocalyptic number.

It is an amenable number.

216530562621 is a deficient number, since it is larger than the sum of its proper divisors (72176854211).

216530562621 is an equidigital number, since it uses as much as digits as its factorization.

216530562621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72176854210.

The product of its (nonzero) digits is 129600, while the sum is 39.

The spelling of 216530562621 in words is "two hundred sixteen billion, five hundred thirty million, five hundred sixty-two thousand, six hundred twenty-one".