13640505 has 16 divisors (see below), whose sum is σ = 22196160. Its totient is φ = 7151168.

The previous prime is 13640491. The next prime is 13640509. The reversal of 13640505 is 50504631.

It is a cyclic number.

It is not a de Polignac number, because 13640505 - 2⁴ = 13640489 is a prime.

It is not an unprimeable number, because it can be changed into a prime (13640509) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6822 + ... + 8591.

It is an arithmetic number, because the mean of its divisors is an integer number (1387260).

Almost surely, 2^13640505 is an apocalyptic number.

13640505 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

13640505 is a deficient number, since it is larger than the sum of its proper divisors (8555655).

13640505 is a wasteful number, since it uses less digits than its factorization.

13640505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15480.

The product of its (nonzero) digits is 1800, while the sum is 24.

The square root of 13640505 is about 3693.3054300992. The cubic root of 13640505 is about 238.9333742847.

The spelling of 13640505 in words is "thirteen million, six hundred forty thousand, five hundred five".