15780816430849 has 4 divisors (see below), whose sum is σ = 15796303003440. Its totient is φ = 15765329858260.

The previous prime is 15780816430787. The next prime is 15780816430861. The reversal of 15780816430849 is 94803461808751.

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-15780816430849 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15780816430879) 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, 7743284767 + ... + 7743286804.

It is an arithmetic number, because the mean of its divisors is an integer number (3949075750860).

Almost surely, 2^{15780816430849} is an apocalyptic number.

It is an amenable number.

15780816430849 is a deficient number, since it is larger than the sum of its proper divisors (15486572591).

15780816430849 is a wasteful number, since it uses less digits than its factorization.

15780816430849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15486572590.

The product of its (nonzero) digits is 46448640, while the sum is 64.

The spelling of 15780816430849 in words is "fifteen trillion, seven hundred eighty billion, eight hundred sixteen million, four hundred thirty thousand, eight hundred forty-nine".