206450221660154 has 4 divisors (see below), whose sum is σ = 309675332490234. Its totient is φ = 103225110830076.

The previous prime is 206450221660051. The next prime is 206450221660157. The reversal of 206450221660154 is 451066122054602.

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

It can be written as a sum of positive squares in only one way, i.e., 190003425293929 + 16446796366225 = 13784173^2 + 4055465^2 .

It is not an unprimeable number, because it can be changed into a prime (206450221660157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 51612555415037 + ... + 51612555415040.

Almost surely, 2^{206450221660154} is an apocalyptic number.

206450221660154 is a deficient number, since it is larger than the sum of its proper divisors (103225110830080).

206450221660154 is a wasteful number, since it uses less digits than its factorization.

206450221660154 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103225110830079.

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

The spelling of 206450221660154 in words is "two hundred six trillion, four hundred fifty billion, two hundred twenty-one million, six hundred sixty thousand, one hundred fifty-four".