13784403649 has 9 divisors (see below), whose sum is σ = 13920867363. Its totient is φ = 13649268192.

The previous prime is 13784403617. The next prime is 13784403653. The reversal of 13784403649 is 94630448731.

The square root of 13784403649 is 117407.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 242892225 + 13541511424 = 15585^2 + 116368^2 .

It is not a de Polignac number, because 13784403649 - 2⁵ = 13784403617 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13784403349) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 13266472 + ... + 13267510.

Almost surely, 2^13784403649 is an apocalyptic number.

13784403649 is the 117407-th square number.

13784403649 is the 58704-th centered octagonal number.

It is an amenable number.

13784403649 is a deficient number, since it is larger than the sum of its proper divisors (136463714).

13784403649 is an frugal number, since it uses more digits than its factorization.

13784403649 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2304 (or 1152 counting only the distinct ones).

The product of its (nonzero) digits is 1741824, while the sum is 49.

Multiplying 13784403649 by its sum of digits (49), we get a square (675435778801 = 821849²).

The spelling of 13784403649 in words is "thirteen billion, seven hundred eighty-four million, four hundred three thousand, six hundred forty-nine".