20605138 has 8 divisors (see below), whose sum is σ = 31973580. Its totient is φ = 9947280.

The previous prime is 20605099. The next prime is 20605147. The reversal of 20605138 is 83150602.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 20133169 + 471969 = 4487^2 + 687^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 177573 + ... + 177688.

Almost surely, 2^20605138 is an apocalyptic number.

20605138 is a deficient number, since it is larger than the sum of its proper divisors (11368442).

20605138 is a wasteful number, since it uses less digits than its factorization.

20605138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 355292.

The product of its (nonzero) digits is 1440, while the sum is 25.

The square root of 20605138 is about 4539.2882702027. The cubic root of 20605138 is about 274.1522676490.

The spelling of 20605138 in words is "twenty million, six hundred five thousand, one hundred thirty-eight".