11781611085 has 32 divisors (see below), whose sum is σ = 19053066240. Its totient is φ = 6216240128.

The previous prime is 11781611069. The next prime is 11781611111. The reversal of 11781611085 is 58011618711.

It is a cyclic number.

It is not a de Polignac number, because 11781611085 - 2⁴ = 11781611069 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 937876 + ... + 950354.

It is an arithmetic number, because the mean of its divisors is an integer number (595408320).

Almost surely, 2^11781611085 is an apocalyptic number.

11781611085 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

11781611085 is a deficient number, since it is larger than the sum of its proper divisors (7271455155).

11781611085 is a wasteful number, since it uses less digits than its factorization.

11781611085 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13157.

The product of its (nonzero) digits is 13440, while the sum is 39.

The spelling of 11781611085 in words is "eleven billion, seven hundred eighty-one million, six hundred eleven thousand, eighty-five".