20820097 has 4 divisors (see below), whose sum is σ = 21173040. Its totient is φ = 20467156.

The previous prime is 20820077. The next prime is 20820101. The reversal of 20820097 is 79002802.

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, and also an emirpimes, since its reverse is a distinct semiprime: 79002802 = 2 ⋅39501401.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20820097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20820017) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 176383 + ... + 176500.

It is an arithmetic number, because the mean of its divisors is an integer number (5293260).

Almost surely, 2^20820097 is an apocalyptic number.

It is an amenable number.

20820097 is a deficient number, since it is larger than the sum of its proper divisors (352943).

20820097 is an equidigital number, since it uses as much as digits as its factorization.

20820097 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 352942.

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 20820097 is about 4562.9044478271. The cubic root of 20820097 is about 275.1023178493.

Adding to 20820097 its reverse (79002802), we get a palindrome (99822899).

The spelling of 20820097 in words is "twenty million, eight hundred twenty thousand, ninety-seven".