1215552555 has 64 divisors (see below), whose sum is σ = 2520192000. Its totient is φ = 555660000.

The previous prime is 1215552529. The next prime is 1215552557. The reversal of 1215552555 is 5552555121.

1215552555 is a `hidden beast` number, since 1 + 2 + 1 + 55 + 52 + 555 = 666.

It is not a de Polignac number, because 1215552555 - 2⁶ = 1215552491 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1215552557) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 33180 + ... + 59430.

It is an arithmetic number, because the mean of its divisors is an integer number (39378000).

Almost surely, 2^1215552555 is an apocalyptic number.

1215552555 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1215552555 is an abundant number, since it is smaller than the sum of its proper divisors (1304639445).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1215552555 is an equidigital number, since it uses as much as digits as its factorization.

1215552555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26286 (or 26266 counting only the distinct ones).

The product of its digits is 62500, while the sum is 36.

The square root of 1215552555 is about 34864.7752753406. The cubic root of 1215552555 is about 1067.2297264349.

The spelling of 1215552555 in words is "one billion, two hundred fifteen million, five hundred fifty-two thousand, five hundred fifty-five".