1216115138 has 8 divisors (see below), whose sum is σ = 2084768832. Its totient is φ = 521192196.

The previous prime is 1216115137. The next prime is 1216115171. The reversal of 1216115138 is 8315116121.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1216115138.

It is not an unprimeable number, because it can be changed into a prime (1216115137) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43432670 + ... + 43432697.

It is an arithmetic number, because the mean of its divisors is an integer number (260596104).

Almost surely, 2^1216115138 is an apocalyptic number.

1216115138 is a deficient number, since it is larger than the sum of its proper divisors (868653694).

1216115138 is an equidigital number, since it uses as much as digits as its factorization.

1216115138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 86865376.

The product of its digits is 1440, while the sum is 29.

The square root of 1216115138 is about 34872.8424135458. The cubic root of 1216115138 is about 1067.3943464112.

The spelling of 1216115138 in words is "one billion, two hundred sixteen million, one hundred fifteen thousand, one hundred thirty-eight".