15219081987 has 4 divisors (see below), whose sum is σ = 20292109320. Its totient is φ = 10146054656.

The previous prime is 15219081979. The next prime is 15219082009. The reversal of 15219081987 is 78918091251.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 78918091251 = 3 ⋅26306030417.

It is a cyclic number.

It is not a de Polignac number, because 15219081987 - 2³ = 15219081979 is a prime.

It is not an unprimeable number, because it can be changed into a prime (15219081287) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2536513662 + ... + 2536513667.

It is an arithmetic number, because the mean of its divisors is an integer number (5073027330).

Almost surely, 2^15219081987 is an apocalyptic number.

15219081987 is a deficient number, since it is larger than the sum of its proper divisors (5073027333).

15219081987 is an equidigital number, since it uses as much as digits as its factorization.

15219081987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5073027332.

The product of its (nonzero) digits is 362880, while the sum is 51.

The spelling of 15219081987 in words is "fifteen billion, two hundred nineteen million, eighty-one thousand, nine hundred eighty-seven".