1201215566 has 16 divisors (see below), whose sum is σ = 1841292864. Its totient is φ = 587467104.

The previous prime is 1201215553. The next prime is 1201215569. The reversal of 1201215566 is 6655121021.

It is a happy 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 (1201215569) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 212756 + ... + 218328.

It is an arithmetic number, because the mean of its divisors is an integer number (115080804).

Almost surely, 2^1201215566 is an apocalyptic number.

1201215566 is a deficient number, since it is larger than the sum of its proper divisors (640077298).

1201215566 is a wasteful number, since it uses less digits than its factorization.

1201215566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7915.

The product of its (nonzero) digits is 3600, while the sum is 29.

The square root of 1201215566 is about 34658.5568943659. The cubic root of 1201215566 is about 1063.0172624351.

Adding to 1201215566 its reverse (6655121021), we get a palindrome (7856336587).

The spelling of 1201215566 in words is "one billion, two hundred one million, two hundred fifteen thousand, five hundred sixty-six".