1217132555 has 4 divisors (see below), whose sum is σ = 1460559072. Its totient is φ = 973706040.

The previous prime is 1217132549. The next prime is 1217132557. The reversal of 1217132555 is 5552317121.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 1217132555 - 2⁶ = 1217132491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1217132557) 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, 121713251 + ... + 121713260.

It is an arithmetic number, because the mean of its divisors is an integer number (365139768).

Almost surely, 2^1217132555 is an apocalyptic number.

1217132555 is a deficient number, since it is larger than the sum of its proper divisors (243426517).

1217132555 is an equidigital number, since it uses as much as digits as its factorization.

1217132555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 243426516.

The product of its digits is 10500, while the sum is 32.

The square root of 1217132555 is about 34887.4268899270. The cubic root of 1217132555 is about 1067.6919285537.

Adding to 1217132555 its reverse (5552317121), we get a palindrome (6769449676).

The spelling of 1217132555 in words is "one billion, two hundred seventeen million, one hundred thirty-two thousand, five hundred fifty-five".