77800061 has 4 divisors (see below), whose sum is σ = 77882652. Its totient is φ = 77717472.

The previous prime is 77800057. The next prime is 77800081. The reversal of 77800061 is 16000877.

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 43811161 + 33988900 = 6619^2 + 5830^2 .

It is a cyclic number.

It is not a de Polignac number, because 77800061 - 2² = 77800057 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 77799997 and 77800033.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77800081) 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 3 ways as a sum of consecutive naturals, for example, 39866 + ... + 41771.

It is an arithmetic number, because the mean of its divisors is an integer number (19470663).

Almost surely, 2^77800061 is an apocalyptic number.

It is an amenable number.

77800061 is a deficient number, since it is larger than the sum of its proper divisors (82591).

77800061 is an equidigital number, since it uses as much as digits as its factorization.

77800061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82590.

The product of its (nonzero) digits is 2352, while the sum is 29.

The square root of 77800061 is about 8820.4342863603. The cubic root of 77800061 is about 426.9004826702.

The spelling of 77800061 in words is "seventy-seven million, eight hundred thousand, sixty-one".