1205561197 has 4 divisors (see below), whose sum is σ = 1207765696. Its totient is φ = 1203356700.

The previous prime is 1205561173. The next prime is 1205561207. The reversal of 1205561197 is 7911655021.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1205561197 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1205567197) 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, 1101429 + ... + 1102522.

It is an arithmetic number, because the mean of its divisors is an integer number (301941424).

Almost surely, 2^1205561197 is an apocalyptic number.

It is an amenable number.

1205561197 is a deficient number, since it is larger than the sum of its proper divisors (2204499).

1205561197 is an equidigital number, since it uses as much as digits as its factorization.

1205561197 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2204498.

The product of its (nonzero) digits is 18900, while the sum is 37.

The square root of 1205561197 is about 34721.1923326374. The cubic root of 1205561197 is about 1064.2976102887.

The spelling of 1205561197 in words is "one billion, two hundred five million, five hundred sixty-one thousand, one hundred ninety-seven".