20215870 has 16 divisors (see below), whose sum is σ = 37276848. Its totient is φ = 7888960.

The previous prime is 20215861. The next prime is 20215879. The reversal of 20215870 is 7851202.

It is an interprime number because it is at equal distance from previous prime (20215861) and next prime (20215879).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20215879) 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 7 ways as a sum of consecutive naturals, for example, 24244 + ... + 25063.

It is an arithmetic number, because the mean of its divisors is an integer number (2329803).

Almost surely, 2^20215870 is an apocalyptic number.

20215870 is a deficient number, since it is larger than the sum of its proper divisors (17060978).

20215870 is a wasteful number, since it uses less digits than its factorization.

20215870 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49355.

The product of its (nonzero) digits is 1120, while the sum is 25.

The square root of 20215870 is about 4496.2061785465. The cubic root of 20215870 is about 272.4148711444.

The spelling of 20215870 in words is "twenty million, two hundred fifteen thousand, eight hundred seventy".