20638149 has 8 divisors (see below), whose sum is σ = 31448640. Its totient is φ = 11793216.

The previous prime is 20638127. The next prime is 20638171. The reversal of 20638149 is 94183602.

It is an interprime number because it is at equal distance from previous prime (20638127) and next prime (20638171).

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

It is not a de Polignac number, because 20638149 - 2¹⁶ = 20572613 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20638109) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 491364 + ... + 491405.

It is an arithmetic number, because the mean of its divisors is an integer number (3931080).

Almost surely, 2^20638149 is an apocalyptic number.

It is an amenable number.

20638149 is a deficient number, since it is larger than the sum of its proper divisors (10810491).

20638149 is an equidigital number, since it uses as much as digits as its factorization.

20638149 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 982779.

The product of its (nonzero) digits is 10368, while the sum is 33.

The square root of 20638149 is about 4542.9229577443. The cubic root of 20638149 is about 274.2985938040.

The spelling of 20638149 in words is "twenty million, six hundred thirty-eight thousand, one hundred forty-nine".