1216534125 has 32 divisors (see below), whose sum is σ = 2037305088. Its totient is φ = 644654400.

The previous prime is 1216534117. The next prime is 1216534129. The reversal of 1216534125 is 5214356121.

It is not a de Polignac number, because 1216534125 - 2³ = 1216534117 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1216534092 and 1216534101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1216534129) 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, 48544 + ... + 69206.

It is an arithmetic number, because the mean of its divisors is an integer number (63665784).

Almost surely, 2^1216534125 is an apocalyptic number.

1216534125 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1216534125 is a deficient number, since it is larger than the sum of its proper divisors (820770963).

1216534125 is a wasteful number, since it uses less digits than its factorization.

1216534125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20838 (or 20828 counting only the distinct ones).

The product of its digits is 7200, while the sum is 30.

The square root of 1216534125 is about 34878.8492499394. The cubic root of 1216534125 is about 1067.5169151248.

The spelling of 1216534125 in words is "one billion, two hundred sixteen million, five hundred thirty-four thousand, one hundred twenty-five".