20638398 has 16 divisors (see below), whose sum is σ = 45029376. Its totient is φ = 6254040.

The previous prime is 20638379. The next prime is 20638417. The reversal of 20638398 is 89383602.

It is an interprime number because it is at equal distance from previous prime (20638379) and next prime (20638417).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 156286 + ... + 156417.

It is an arithmetic number, because the mean of its divisors is an integer number (2814336).

Almost surely, 2^20638398 is an apocalyptic number.

20638398 is an abundant number, since it is smaller than the sum of its proper divisors (24390978).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20638398 is a wasteful number, since it uses less digits than its factorization.

20638398 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 312719.

The product of its (nonzero) digits is 62208, while the sum is 39.

The square root of 20638398 is about 4542.9503629250. The cubic root of 20638398 is about 274.2996969403.

The spelling of 20638398 in words is "twenty million, six hundred thirty-eight thousand, three hundred ninety-eight".