691868100811 has 4 divisors (see below), whose sum is σ = 728282211400. Its totient is φ = 655453990224.

The previous prime is 691868100797. The next prime is 691868100817. The reversal of 691868100811 is 118001868196.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 691868100811 - 2⁷ = 691868100683 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (691868100817) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18207055266 + ... + 18207055303.

It is an arithmetic number, because the mean of its divisors is an integer number (182070552850).

Almost surely, 2^691868100811 is an apocalyptic number.

691868100811 is a deficient number, since it is larger than the sum of its proper divisors (36414110589).

691868100811 is a wasteful number, since it uses less digits than its factorization.

691868100811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36414110588.

The product of its (nonzero) digits is 165888, while the sum is 49.

The spelling of 691868100811 in words is "six hundred ninety-one billion, eight hundred sixty-eight million, one hundred thousand, eight hundred eleven".