1215501255 has 16 divisors (see below), whose sum is σ = 2160891360. Its totient is φ = 648267264.

The previous prime is 1215501247. The next prime is 1215501257. The reversal of 1215501255 is 5521055121.

It is not a de Polignac number, because 1215501255 - 2³ = 1215501247 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1215501257) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4501722 + ... + 4501991.

It is an arithmetic number, because the mean of its divisors is an integer number (135055710).

Almost surely, 2^1215501255 is an apocalyptic number.

1215501255 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1215501255 is a deficient number, since it is larger than the sum of its proper divisors (945390105).

1215501255 is an equidigital number, since it uses as much as digits as its factorization.

1215501255 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9003727 (or 9003721 counting only the distinct ones).

The product of its (nonzero) digits is 2500, while the sum is 27.

The square root of 1215501255 is about 34864.0395680133. The cubic root of 1215501255 is about 1067.2147127813.

Adding to 1215501255 its reverse (5521055121), we get a palindrome (6736556376).

The spelling of 1215501255 in words is "one billion, two hundred fifteen million, five hundred one thousand, two hundred fifty-five".