11681506605 has 16 divisors (see below), whose sum is σ = 19043061120. Its totient is φ = 6112586688.

The previous prime is 11681506597. The next prime is 11681506619. The reversal of 11681506605 is 50660518611.

It is not a de Polignac number, because 11681506605 - 2³ = 11681506597 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 7346065 + ... + 7347654.

It is an arithmetic number, because the mean of its divisors is an integer number (1190191320).

Almost surely, 2^11681506605 is an apocalyptic number.

11681506605 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

11681506605 is a deficient number, since it is larger than the sum of its proper divisors (7361554515).

11681506605 is a wasteful number, since it uses less digits than its factorization.

11681506605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14693780.

The product of its (nonzero) digits is 43200, while the sum is 39.

The spelling of 11681506605 in words is "eleven billion, six hundred eighty-one million, five hundred six thousand, six hundred five".