321940691 has 4 divisors (see below), whose sum is σ = 321982800. Its totient is φ = 321898584.

The previous prime is 321940681. The next prime is 321940739. The reversal of 321940691 is 196049123.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 321940691 - 2⁶ = 321940627 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (321940681) 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, 5996 + ... + 26073.

It is an arithmetic number, because the mean of its divisors is an integer number (80495700).

Almost surely, 2^321940691 is an apocalyptic number.

321940691 is a deficient number, since it is larger than the sum of its proper divisors (42109).

321940691 is a wasteful number, since it uses less digits than its factorization.

321940691 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42108.

The product of its (nonzero) digits is 11664, while the sum is 35.

The square root of 321940691 is about 17942.7057881469. The cubic root of 321940691 is about 685.3703156904.

The spelling of 321940691 in words is "three hundred twenty-one million, nine hundred forty thousand, six hundred ninety-one".