20018378 has 4 divisors (see below), whose sum is σ = 30027570. Its totient is φ = 10009188.

The previous prime is 20018377. The next prime is 20018393. The reversal of 20018378 is 87381002.

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

It can be written as a sum of positive squares in only one way, i.e., 17698849 + 2319529 = 4207^2 + 1523^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 20018378.

It is not an unprimeable number, because it can be changed into a prime (20018377) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5004593 + ... + 5004596.

Almost surely, 2^20018378 is an apocalyptic number.

20018378 is a deficient number, since it is larger than the sum of its proper divisors (10009192).

20018378 is a wasteful number, since it uses less digits than its factorization.

20018378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10009191.

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 20018378 is about 4474.1902060596. The cubic root of 20018378 is about 271.5248788175.

The spelling of 20018378 in words is "twenty million, eighteen thousand, three hundred seventy-eight".