20221865 has 8 divisors (see below), whose sum is σ = 24608448. Its totient is φ = 15949360.

The previous prime is 20221849. The next prime is 20221879. The reversal of 20221865 is 56812202.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 20221865 - 2⁴ = 20221849 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 28127 + ... + 28836.

It is an arithmetic number, because the mean of its divisors is an integer number (3076056).

Almost surely, 2^20221865 is an apocalyptic number.

It is an amenable number.

20221865 is a deficient number, since it is larger than the sum of its proper divisors (4386583).

20221865 is an equidigital number, since it uses as much as digits as its factorization.

20221865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57039.

The product of its (nonzero) digits is 1920, while the sum is 26.

The square root of 20221865 is about 4496.8728022927. The cubic root of 20221865 is about 272.4417966201.

The spelling of 20221865 in words is "twenty million, two hundred twenty-one thousand, eight hundred sixty-five".