20078215 has 4 divisors (see below), whose sum is σ = 24093864. Its totient is φ = 16062568.

The previous prime is 20078213. The next prime is 20078249. The reversal of 20078215 is 51287002.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20078215 - 2¹ = 20078213 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20078215.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20078213) 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 3 ways as a sum of consecutive naturals, for example, 2007817 + ... + 2007826.

It is an arithmetic number, because the mean of its divisors is an integer number (6023466).

Almost surely, 2^20078215 is an apocalyptic number.

20078215 is a deficient number, since it is larger than the sum of its proper divisors (4015649).

20078215 is an equidigital number, since it uses as much as digits as its factorization.

20078215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4015648.

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

The square root of 20078215 is about 4480.8721249328. The cubic root of 20078215 is about 271.7951483465.

The spelling of 20078215 in words is "twenty million, seventy-eight thousand, two hundred fifteen".