1216715136 has 128 divisors (see below), whose sum is σ = 3977836800. Its totient is φ = 320882688.

The previous prime is 1216715081. The next prime is 1216715147. The reversal of 1216715136 is 6315176121.

It is a tau number, because it is divible by the number of its divisors (128).

It is a junction number, because it is equal to n+sod(n) for n = 1216715097 and 1216715106.

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, 17535 + ... + 52353.

It is an arithmetic number, because the mean of its divisors is an integer number (31076850).

Almost surely, 2^1216715136 is an apocalyptic number.

1216715136 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1216715136, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1988918400).

1216715136 is an abundant number, since it is smaller than the sum of its proper divisors (2761121664).

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

1216715136 is a wasteful number, since it uses less digits than its factorization.

1216715136 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34856 (or 34844 counting only the distinct ones).

The product of its digits is 7560, while the sum is 33.

The square root of 1216715136 is about 34881.4440068068. Note that the first 3 decimals coincide. The cubic root of 1216715136 is about 1067.5698586243.

The spelling of 1216715136 in words is "one billion, two hundred sixteen million, seven hundred fifteen thousand, one hundred thirty-six".