239806981 has 8 divisors (see below), whose sum is σ = 255533400. Its totient is φ = 224260608.

The previous prime is 239806951. The next prime is 239807021. The reversal of 239806981 is 189608932.

It can be written as a sum of positive squares in 4 ways, for example, as 47541025 + 192265956 = 6895^2 + 13866^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 239806981 - 2¹³ = 239798789 is a prime.

It is a super-2 number, since 2×239806981² = 115014776272668722, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (239806951) 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, 42256 + ... + 47593.

It is an arithmetic number, because the mean of its divisors is an integer number (31941675).

Almost surely, 2^239806981 is an apocalyptic number.

It is an amenable number.

239806981 is a deficient number, since it is larger than the sum of its proper divisors (15726419).

239806981 is a wasteful number, since it uses less digits than its factorization.

239806981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90023.

The product of its (nonzero) digits is 186624, while the sum is 46.

The square root of 239806981 is about 15485.7024703434. The cubic root of 239806981 is about 621.2798579223.

The spelling of 239806981 in words is "two hundred thirty-nine million, eight hundred six thousand, nine hundred eighty-one".