77605961 has 2 divisors, whose sum is σ = 77605962. Its totient is φ = 77605960.

The previous prime is 77605921. The next prime is 77605963. The reversal of 77605961 is 16950677.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 49843600 + 27762361 = 7060^2 + 5269^2 .

It is a cyclic number.

It is not a de Polignac number, because 77605961 - 2¹⁸ = 77343817 is a prime.

Together with 77605963, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (77605963) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 38802980 + 38802981.

It is an arithmetic number, because the mean of its divisors is an integer number (38802981).

Almost surely, 2^77605961 is an apocalyptic number.

It is an amenable number.

77605961 is a deficient number, since it is larger than the sum of its proper divisors (1).

77605961 is an equidigital number, since it uses as much as digits as its factorization.

77605961 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 79380, while the sum is 41.

The square root of 77605961 is about 8809.4245555541. The cubic root of 77605961 is about 426.5451685168.

The spelling of 77605961 in words is "seventy-seven million, six hundred five thousand, nine hundred sixty-one".