20617258 has 4 divisors (see below), whose sum is σ = 30925890. Its totient is φ = 10308628.

The previous prime is 20617249. The next prime is 20617271. The reversal of 20617258 is 85271602.

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., 20548089 + 69169 = 4533^2 + 263^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5154313 + ... + 5154316.

Almost surely, 2^20617258 is an apocalyptic number.

20617258 is a deficient number, since it is larger than the sum of its proper divisors (10308632).

20617258 is a wasteful number, since it uses less digits than its factorization.

20617258 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10308631.

The product of its (nonzero) digits is 6720, while the sum is 31.

The square root of 20617258 is about 4540.6230849962. The cubic root of 20617258 is about 274.2060094911.

The spelling of 20617258 in words is "twenty million, six hundred seventeen thousand, two hundred fifty-eight".