806087781 has 10 divisors (see below), whose sum is σ = 1204155942. Its totient is φ = 537391800.

The previous prime is 806087747. The next prime is 806087801. The reversal of 806087781 is 187780608.

It can be written as a sum of positive squares in only one way, i.e., 543356100 + 262731681 = 23310^2 + 16209^2 .

It is not a de Polignac number, because 806087781 - 2¹⁴ = 806071397 is a prime.

It is a super-3 number, since 3×806087781³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (806087701) by changing a digit.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 4975770 + ... + 4975931.

Almost surely, 2^806087781 is an apocalyptic number.

806087781 is a gapful number since it is divisible by the number (81) formed by its first and last digit.

It is an amenable number.

806087781 is a deficient number, since it is larger than the sum of its proper divisors (398068161).

806087781 is an equidigital number, since it uses as much as digits as its factorization.

806087781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9951713 (or 9951704 counting only the distinct ones).

The product of its (nonzero) digits is 150528, while the sum is 45.

The square root of 806087781 is about 28391.6850679913. The cubic root of 806087781 is about 930.6665668767. Note that the first 3 decimals are identical.

The spelling of 806087781 in words is "eight hundred six million, eighty-seven thousand, seven hundred eighty-one".