80766709 has 4 divisors (see below), whose sum is σ = 80786860. Its totient is φ = 80746560.

The previous prime is 80766683. The next prime is 80766797. The reversal of 80766709 is 90766708.

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 18404100 + 62362609 = 4290^2 + 7897^2 .

It is a cyclic number.

It is not a de Polignac number, because 80766709 - 2²³ = 72378101 is a prime.

It is a super-2 number, since 2×80766709² = 13046522565381362, 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 (80760709) 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, 1794 + ... + 12835.

It is an arithmetic number, because the mean of its divisors is an integer number (20196715).

Almost surely, 2^80766709 is an apocalyptic number.

It is an amenable number.

80766709 is a deficient number, since it is larger than the sum of its proper divisors (20151).

80766709 is a wasteful number, since it uses less digits than its factorization.

80766709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20150.

The product of its (nonzero) digits is 127008, while the sum is 43.

The square root of 80766709 is about 8987.0300433458. The cubic root of 80766709 is about 432.2590841998.

Subtracting 80766709 from its reverse (90766708), we obtain a palindrome (9999999).

The spelling of 80766709 in words is "eighty million, seven hundred sixty-six thousand, seven hundred nine".