1185217121 has 4 divisors (see below), whose sum is σ = 1292964144. Its totient is φ = 1077470100.

The previous prime is 1185217097. The next prime is 1185217133. The reversal of 1185217121 is 1217125811.

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 not a de Polignac number, because 1185217121 - 2¹⁸ = 1184954977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1185217421) 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, 53873495 + ... + 53873516.

It is an arithmetic number, because the mean of its divisors is an integer number (323241036).

Almost surely, 2^1185217121 is an apocalyptic number.

1185217121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1185217121 is a deficient number, since it is larger than the sum of its proper divisors (107747023).

1185217121 is a wasteful number, since it uses less digits than its factorization.

1185217121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 107747022.

The product of its digits is 1120, while the sum is 29.

The square root of 1185217121 is about 34426.9824556263. The cubic root of 1185217121 is about 1058.2768731958.

The spelling of 1185217121 in words is "one billion, one hundred eighty-five million, two hundred seventeen thousand, one hundred twenty-one".