691921795 has 4 divisors (see below), whose sum is σ = 830306160. Its totient is φ = 553537432.

The previous prime is 691921753. The next prime is 691921799. The reversal of 691921795 is 597129196.

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 691921795 - 2¹¹ = 691919747 is a prime.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (691921799) 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, 69192175 + ... + 69192184.

It is an arithmetic number, because the mean of its divisors is an integer number (207576540).

Almost surely, 2^691921795 is an apocalyptic number.

691921795 is a deficient number, since it is larger than the sum of its proper divisors (138384365).

691921795 is a wasteful number, since it uses less digits than its factorization.

691921795 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138384364.

The product of its digits is 306180, while the sum is 49.

The square root of 691921795 is about 26304.4063799205. The cubic root of 691921795 is about 884.4752206050.

The spelling of 691921795 in words is "six hundred ninety-one million, nine hundred twenty-one thousand, seven hundred ninety-five".