76720081 has 9 divisors (see below), whose sum is σ = 81146523. Its totient is φ = 72524520.

The previous prime is 76720067. The next prime is 76720103. The reversal of 76720081 is 18002767.

It is a happy number.

The square root of 76720081 is 8759.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 24591681 + 52128400 = 4959^2 + 7220^2 .

It is not a de Polignac number, because 76720081 - 2¹⁹ = 76195793 is a prime.

It is a super-2 number, since 2×76720081² = 11771941657293122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (76720481) 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 8 ways as a sum of consecutive naturals, for example, 166191 + ... + 166651.

Almost surely, 2^76720081 is an apocalyptic number.

76720081 is the 8759-th square number.

76720081 is the 4380-th centered octagonal number.

It is an amenable number.

76720081 is a deficient number, since it is larger than the sum of its proper divisors (4426442).

76720081 is an frugal number, since it uses more digits than its factorization.

76720081 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 960 (or 480 counting only the distinct ones).

The product of its (nonzero) digits is 4704, while the sum is 31.

The cubic root of 76720081 is about 424.9159344686.

The spelling of 76720081 in words is "seventy-six million, seven hundred twenty thousand, eighty-one".