1211511117 has 8 divisors (see below), whose sum is σ = 1700366560. Its totient is φ = 765164880.

The previous prime is 1211511109. The next prime is 1211511121. The reversal of 1211511117 is 7111151121.

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

It is not a de Polignac number, because 1211511117 - 2³ = 1211511109 is a prime.

It is a super-2 number, since 2×1211511117² = 2935518373229175378, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1211511093 and 1211511102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211511317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10627234 + ... + 10627347.

It is an arithmetic number, because the mean of its divisors is an integer number (212545820).

Almost surely, 2^1211511117 is an apocalyptic number.

It is an amenable number.

1211511117 is a deficient number, since it is larger than the sum of its proper divisors (488855443).

1211511117 is a wasteful number, since it uses less digits than its factorization.

1211511117 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21254603.

The product of its digits is 70, while the sum is 21.

The square root of 1211511117 is about 34806.7682642327. The cubic root of 1211511117 is about 1066.0456471787.

Adding to 1211511117 its reverse (7111151121), we get a palindrome (8322662238).

It can be divided in two parts, 12115 and 11117, that added together give a palindrome (23232).

The spelling of 1211511117 in words is "one billion, two hundred eleven million, five hundred eleven thousand, one hundred seventeen".