1255121215 has 16 divisors (see below), whose sum is σ = 1549539072. Its totient is φ = 975262464.

The previous prime is 1255121207. The next prime is 1255121221. The reversal of 1255121215 is 5121215521.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1255121215 - 2³ = 1255121207 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1255121215.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 106707 + ... + 117883.

It is an arithmetic number, because the mean of its divisors is an integer number (96846192).

Almost surely, 2^1255121215 is an apocalyptic number.

1255121215 is a deficient number, since it is larger than the sum of its proper divisors (294417857).

1255121215 is a wasteful number, since it uses less digits than its factorization.

1255121215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11826.

The product of its digits is 1000, while the sum is 25.

The square root of 1255121215 is about 35427.6899472715. The cubic root of 1255121215 is about 1078.6864503112.

Adding to 1255121215 its reverse (5121215521), we get a palindrome (6376336736).

The spelling of 1255121215 in words is "one billion, two hundred fifty-five million, one hundred twenty-one thousand, two hundred fifteen".