806239981 has 4 divisors (see below), whose sum is σ = 824989792. Its totient is φ = 787490172.

The previous prime is 806239969. The next prime is 806240047. The reversal of 806239981 is 189932608.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 806239981 - 2¹¹ = 806237933 is a prime.

It is a super-2 number, since 2×806239981² = 1300045813925760722, 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 (806239921) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9374841 + ... + 9374926.

It is an arithmetic number, because the mean of its divisors is an integer number (206247448).

Almost surely, 2^806239981 is an apocalyptic number.

It is an amenable number.

806239981 is a deficient number, since it is larger than the sum of its proper divisors (18749811).

806239981 is a wasteful number, since it uses less digits than its factorization.

806239981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18749810.

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

The square root of 806239981 is about 28394.3653037007. The cubic root of 806239981 is about 930.7251372296.

The spelling of 806239981 in words is "eight hundred six million, two hundred thirty-nine thousand, nine hundred eighty-one".