16580781553 has 16 divisors (see below), whose sum is σ = 19785884800. Its totient is φ = 13881572208.

The previous prime is 16580781541. The next prime is 16580781557. The reversal of 16580781553 is 35518708561.

It is not a de Polignac number, because 16580781553 - 2¹³ = 16580773361 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (49).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16580781497 and 16580781506.

It is not an unprimeable number, because it can be changed into a prime (16580781557) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 547350 + ... + 576847.

It is an arithmetic number, because the mean of its divisors is an integer number (1236617800).

Almost surely, 2^16580781553 is an apocalyptic number.

It is an amenable number.

16580781553 is a deficient number, since it is larger than the sum of its proper divisors (3205103247).

16580781553 is an equidigital number, since it uses as much as digits as its factorization.

16580781553 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1124261 (or 1124247 counting only the distinct ones).

The product of its (nonzero) digits is 1008000, while the sum is 49.

The spelling of 16580781553 in words is "sixteen billion, five hundred eighty million, seven hundred eighty-one thousand, five hundred fifty-three".