239135021 has 4 divisors (see below), whose sum is σ = 240658332. Its totient is φ = 237611712.

The previous prime is 239135011. The next prime is 239135041. The reversal of 239135021 is 120531932.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 171976996 + 67158025 = 13114^2 + 8195^2 .

It is a cyclic number.

It is not a de Polignac number, because 239135021 - 2¹⁴ = 239118637 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (239135011) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 761420 + ... + 761733.

It is an arithmetic number, because the mean of its divisors is an integer number (60164583).

Almost surely, 2^239135021 is an apocalyptic number.

It is an amenable number.

239135021 is a deficient number, since it is larger than the sum of its proper divisors (1523311).

239135021 is a wasteful number, since it uses less digits than its factorization.

239135021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1523310.

The product of its (nonzero) digits is 1620, while the sum is 26.

The square root of 239135021 is about 15463.9911083782. The cubic root of 239135021 is about 620.6990216824.

Adding to 239135021 its reverse (120531932), we get a palindrome (359666953).

The spelling of 239135021 in words is "two hundred thirty-nine million, one hundred thirty-five thousand, twenty-one".