1216255271 has 32 divisors (see below), whose sum is σ = 1591136256. Its totient is φ = 902016000.

The previous prime is 1216255253. The next prime is 1216255279. The reversal of 1216255271 is 1725526121.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1216255271 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216255279) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 141431 + ... + 149783.

It is an arithmetic number, because the mean of its divisors is an integer number (49723008).

Almost surely, 2^1216255271 is an apocalyptic number.

1216255271 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1216255271 is a deficient number, since it is larger than the sum of its proper divisors (374880985).

1216255271 is a wasteful number, since it uses less digits than its factorization.

1216255271 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8463.

The product of its digits is 8400, while the sum is 32.

The square root of 1216255271 is about 34874.8515552396. The cubic root of 1216255271 is about 1067.4353434688.

The spelling of 1216255271 in words is "one billion, two hundred sixteen million, two hundred fifty-five thousand, two hundred seventy-one".