1216533513 has 8 divisors (see below), whose sum is σ = 1746817408. Its totient is φ = 748635984.

The previous prime is 1216533491. The next prime is 1216533517. The reversal of 1216533513 is 3153356121.

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

It is not a de Polignac number, because 1216533513 - 2¹⁸ = 1216271369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1216533517) 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, 15596545 + ... + 15596622.

It is an arithmetic number, because the mean of its divisors is an integer number (218352176).

Almost surely, 2^1216533513 is an apocalyptic number.

1216533513 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

It is an amenable number.

1216533513 is a deficient number, since it is larger than the sum of its proper divisors (530283895).

1216533513 is a wasteful number, since it uses less digits than its factorization.

1216533513 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31193183.

The product of its digits is 8100, while the sum is 30.

The square root of 1216533513 is about 34878.8404767131. The cubic root of 1216533513 is about 1067.5167361134.

Adding to 1216533513 its reverse (3153356121), we get a palindrome (4369889634).

The spelling of 1216533513 in words is "one billion, two hundred sixteen million, five hundred thirty-three thousand, five hundred thirteen".