20321197 has 8 divisors (see below), whose sum is σ = 22086680. Its totient is φ = 18584640.

The previous prime is 20321183. The next prime is 20321201. The reversal of 20321197 is 79112302.

It can be written as a sum of positive squares in 4 ways, for example, as 17161 + 20304036 = 131^2 + 4506^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20321197 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 (20321297) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5754 + ... + 8587.

It is an arithmetic number, because the mean of its divisors is an integer number (2760835).

Almost surely, 2^20321197 is an apocalyptic number.

It is an amenable number.

20321197 is a deficient number, since it is larger than the sum of its proper divisors (1765483).

20321197 is a wasteful number, since it uses less digits than its factorization.

20321197 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14463.

The product of its (nonzero) digits is 756, while the sum is 25.

The square root of 20321197 is about 4507.9038365963. The cubic root of 20321197 is about 272.8871561070.

Adding to 20321197 its reverse (79112302), we get a palindrome (99433499).

The spelling of 20321197 in words is "twenty million, three hundred twenty-one thousand, one hundred ninety-seven".