1215206205 has 16 divisors (see below), whose sum is σ = 1946700864. Its totient is φ = 647319680.

The previous prime is 1215206191. The next prime is 1215206221. The reversal of 1215206205 is 5026025121.

It is a happy number.

1215206205 is digitally balanced in base 4, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 1215206205 - 2¹⁰ = 1215205181 is a prime.

It is a super-2 number, since 2×1215206205² = 2953452241341004050, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 36576 + ... + 61385.

It is an arithmetic number, because the mean of its divisors is an integer number (121668804).

Almost surely, 2^1215206205 is an apocalyptic number.

1215206205 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1215206205 is a deficient number, since it is larger than the sum of its proper divisors (731494659).

1215206205 is an equidigital number, since it uses as much as digits as its factorization.

1215206205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98796.

The product of its (nonzero) digits is 1200, while the sum is 24.

The square root of 1215206205 is about 34859.8078738251. The cubic root of 1215206205 is about 1067.1283541203.

The spelling of 1215206205 in words is "one billion, two hundred fifteen million, two hundred six thousand, two hundred five".