206644551461 has 4 divisors (see below), whose sum is σ = 206961006252. Its totient is φ = 206328096672.

The previous prime is 206644551419. The next prime is 206644551499. The reversal of 206644551461 is 164155446602.

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 98646874561 + 107997676900 = 314081^2 + 328630^2 .

It is a cyclic number.

It is not a de Polignac number, because 206644551461 - 2¹⁴ = 206644535077 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (206644551961) 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, 158226416 + ... + 158227721.

It is an arithmetic number, because the mean of its divisors is an integer number (51740251563).

Almost surely, 2^206644551461 is an apocalyptic number.

It is an amenable number.

206644551461 is a deficient number, since it is larger than the sum of its proper divisors (316454791).

206644551461 is an equidigital number, since it uses as much as digits as its factorization.

206644551461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 316454790.

The product of its (nonzero) digits is 691200, while the sum is 44.

The spelling of 206644551461 in words is "two hundred six billion, six hundred forty-four million, five hundred fifty-one thousand, four hundred sixty-one".