20858397 has 16 divisors (see below), whose sum is σ = 32524800. Its totient is φ = 11641392.

The previous prime is 20858389. The next prime is 20858407. The reversal of 20858397 is 79385802.

It is not a de Polignac number, because 20858397 - 2³ = 20858389 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20858317) 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 15 ways as a sum of consecutive naturals, for example, 10647 + ... + 12452.

It is an arithmetic number, because the mean of its divisors is an integer number (2032800).

Almost surely, 2^20858397 is an apocalyptic number.

It is an amenable number.

20858397 is a deficient number, since it is larger than the sum of its proper divisors (11666403).

20858397 is a wasteful number, since it uses less digits than its factorization.

20858397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23152.

The product of its (nonzero) digits is 120960, while the sum is 42.

The square root of 20858397 is about 4567.0994077204. The cubic root of 20858397 is about 275.2709043924.

The spelling of 20858397 in words is "twenty million, eight hundred fifty-eight thousand, three hundred ninety-seven".