216342233561 has 4 divisors (see below), whose sum is σ = 216392867892. Its totient is φ = 216291599232.

The previous prime is 216342233539. The next prime is 216342233603. The reversal of 216342233561 is 165332243612.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 151441614025 + 64900619536 = 389155^2 + 254756^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216342233561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216342233521) 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, 25310756 + ... + 25319301.

It is an arithmetic number, because the mean of its divisors is an integer number (54098216973).

Almost surely, 2^216342233561 is an apocalyptic number.

It is an amenable number.

216342233561 is a deficient number, since it is larger than the sum of its proper divisors (50634331).

216342233561 is an equidigital number, since it uses as much as digits as its factorization.

216342233561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50634330.

The product of its digits is 155520, while the sum is 38.

The spelling of 216342233561 in words is "two hundred sixteen billion, three hundred forty-two million, two hundred thirty-three thousand, five hundred sixty-one".