258505138 has 4 divisors (see below), whose sum is σ = 387757710. Its totient is φ = 129252568.

The previous prime is 258505109. The next prime is 258505141. The reversal of 258505138 is 831505852.

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., 248913729 + 9591409 = 15777^2 + 3097^2 .

It is a junction number, because it is equal to n+sod(n) for n = 258505097 and 258505106.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64626283 + ... + 64626286.

Almost surely, 2^258505138 is an apocalyptic number.

258505138 is a deficient number, since it is larger than the sum of its proper divisors (129252572).

258505138 is a wasteful number, since it uses less digits than its factorization.

258505138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 129252571.

The product of its (nonzero) digits is 48000, while the sum is 37.

The square root of 258505138 is about 16078.0949742188. The cubic root of 258505138 is about 637.0248777155.

The spelling of 258505138 in words is "two hundred fifty-eight million, five hundred five thousand, one hundred thirty-eight".