15118821087 has 4 divisors (see below), whose sum is σ = 20158428120. Its totient is φ = 10079214056.

The previous prime is 15118821071. The next prime is 15118821131. The reversal of 15118821087 is 78012881151.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 15118821087 - 2⁴ = 15118821071 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15118821007) 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, 2519803512 + ... + 2519803517.

It is an arithmetic number, because the mean of its divisors is an integer number (5039607030).

Almost surely, 2^15118821087 is an apocalyptic number.

15118821087 is a deficient number, since it is larger than the sum of its proper divisors (5039607033).

15118821087 is an equidigital number, since it uses as much as digits as its factorization.

15118821087 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5039607032.

The product of its (nonzero) digits is 35840, while the sum is 42.

The spelling of 15118821087 in words is "fifteen billion, one hundred eighteen million, eight hundred twenty-one thousand, eighty-seven".