20897371 has 16 divisors (see below), whose sum is σ = 23839200. Its totient is φ = 18144000.

The previous prime is 20897353. The next prime is 20897377. The reversal of 20897371 is 17379802.

It is a cyclic number.

It is not a de Polignac number, because 20897371 - 2⁷ = 20897243 is a prime.

It is a super-2 number, since 2×20897371² = 873400229423282, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 20897371.

It is not an unprimeable number, because it can be changed into a prime (20897377) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 34471 + ... + 35071.

It is an arithmetic number, because the mean of its divisors is an integer number (1489950).

Almost surely, 2^20897371 is an apocalyptic number.

20897371 is a deficient number, since it is larger than the sum of its proper divisors (2941829).

20897371 is a wasteful number, since it uses less digits than its factorization.

20897371 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 750.

The product of its (nonzero) digits is 21168, while the sum is 37.

The square root of 20897371 is about 4571.3642383866. The cubic root of 20897371 is about 275.4422459890.

It can be divided in two parts, 208 and 97371, that added together give a palindrome (97579).

The spelling of 20897371 in words is "twenty million, eight hundred ninety-seven thousand, three hundred seventy-one".