205212155 has 8 divisors (see below), whose sum is σ = 248135184. Its totient is φ = 162916000.

The previous prime is 205212143. The next prime is 205212173. The reversal of 205212155 is 551212502.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 205212155 - 2²² = 201017851 is a prime.

It is a super-2 number, since 2×205212155² = 84224057119488050, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 205212155.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 155996 + ... + 157305.

It is an arithmetic number, because the mean of its divisors is an integer number (31016898).

Almost surely, 2^205212155 is an apocalyptic number.

205212155 is a deficient number, since it is larger than the sum of its proper divisors (42923029).

205212155 is a wasteful number, since it uses less digits than its factorization.

205212155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 313437.

The product of its (nonzero) digits is 1000, while the sum is 23.

The square root of 205212155 is about 14325.2279213980. The cubic root of 205212155 is about 589.8401894085.

Adding to 205212155 its reverse (551212502), we get a palindrome (756424657).

The spelling of 205212155 in words is "two hundred five million, two hundred twelve thousand, one hundred fifty-five".