20897207 has 12 divisors (see below), whose sum is σ = 22302216. Its totient is φ = 19576080.

The previous prime is 20897147. The next prime is 20897213. The reversal of 20897207 is 70279802.

It is not a de Polignac number, because 20897207 - 2⁶ = 20897143 is a prime.

It is a super-3 number, since 3×20897207³ (a number of 23 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20897237) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 38357 + ... + 38897.

It is an arithmetic number, because the mean of its divisors is an integer number (1858518).

Almost surely, 2^20897207 is an apocalyptic number.

20897207 is a deficient number, since it is larger than the sum of its proper divisors (1405009).

20897207 is a wasteful number, since it uses less digits than its factorization.

20897207 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 686 (or 667 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 35.

The square root of 20897207 is about 4571.3463005990. The cubic root of 20897207 is about 275.4415254415.

The spelling of 20897207 in words is "twenty million, eight hundred ninety-seven thousand, two hundred seven".