15966780989 has 4 divisors (see below), whose sum is σ = 16062390624. Its totient is φ = 15871171356.

The previous prime is 15966780983. The next prime is 15966781031. The reversal of 15966780989 is 98908766951.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15966780989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15966780983) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 47804567 + ... + 47804900.

It is an arithmetic number, because the mean of its divisors is an integer number (4015597656).

Almost surely, 2^15966780989 is an apocalyptic number.

It is an amenable number.

15966780989 is a deficient number, since it is larger than the sum of its proper divisors (95609635).

15966780989 is an equidigital number, since it uses as much as digits as its factorization.

15966780989 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95609634.

The product of its (nonzero) digits is 58786560, while the sum is 68.

The spelling of 15966780989 in words is "fifteen billion, nine hundred sixty-six million, seven hundred eighty thousand, nine hundred eighty-nine".