691823941 has 4 divisors (see below), whose sum is σ = 692356192. Its totient is φ = 691291692.

The previous prime is 691823933. The next prime is 691823987. The reversal of 691823941 is 149328196.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 691823941 - 2³ = 691823933 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (691823641) 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, 264171 + ... + 266776.

It is an arithmetic number, because the mean of its divisors is an integer number (173089048).

Almost surely, 2^691823941 is an apocalyptic number.

It is an amenable number.

691823941 is a deficient number, since it is larger than the sum of its proper divisors (532251).

691823941 is a wasteful number, since it uses less digits than its factorization.

691823941 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 532250.

The product of its digits is 93312, while the sum is 43.

The square root of 691823941 is about 26302.5462835825. The cubic root of 691823941 is about 884.4335234463.

The spelling of 691823941 in words is "six hundred ninety-one million, eight hundred twenty-three thousand, nine hundred forty-one".