13778246545 has 20 divisors (see below), whose sum is σ = 19288414260. Its totient is φ = 9447932256.

The previous prime is 13778246539. The next prime is 13778246561. The reversal of 13778246545 is 54564287731.

It can be written as a sum of positive squares in 2 ways, for example, as 10457721169 + 3320525376 = 102263^2 + 57624^2 .

It is a de Polignac number, because none of the positive numbers 2^k-13778246545 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 13778246492 and 13778246501.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 561850 + ... + 585859.

It is an arithmetic number, because the mean of its divisors is an integer number (964420713).

Almost surely, 2^13778246545 is an apocalyptic number.

It is an amenable number.

13778246545 is a deficient number, since it is larger than the sum of its proper divisors (5510167715).

13778246545 is an frugal number, since it uses more digits than its factorization.

13778246545 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1147742 (or 1147721 counting only the distinct ones).

The product of its digits is 5644800, while the sum is 52.

The spelling of 13778246545 in words is "thirteen billion, seven hundred seventy-eight million, two hundred forty-six thousand, five hundred forty-five".