20873865 has 16 divisors (see below), whose sum is σ = 33474816. Its totient is φ = 11107200.

The previous prime is 20873861. The next prime is 20873869. The reversal of 20873865 is 56837802.

It is an interprime number because it is at equal distance from previous prime (20873861) and next prime (20873869).

It is not a de Polignac number, because 20873865 - 2² = 20873861 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20873861) 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 15 ways as a sum of consecutive naturals, for example, 6480 + ... + 9150.

It is an arithmetic number, because the mean of its divisors is an integer number (2092176).

Almost surely, 2^20873865 is an apocalyptic number.

It is an amenable number.

20873865 is a deficient number, since it is larger than the sum of its proper divisors (12600951).

20873865 is a wasteful number, since it uses less digits than its factorization.

20873865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3200.

The product of its (nonzero) digits is 80640, while the sum is 39.

The square root of 20873865 is about 4568.7925100621. The cubic root of 20873865 is about 275.3389319638.

The spelling of 20873865 in words is "twenty million, eight hundred seventy-three thousand, eight hundred sixty-five".