77799901 has 2 divisors, whose sum is σ = 77799902. Its totient is φ = 77799900.

The previous prime is 77799877. The next prime is 77799913. The reversal of 77799901 is 10999777.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 65367225 + 12432676 = 8085^2 + 3526^2 .

It is a cyclic number.

It is not a de Polignac number, because 77799901 - 2¹³ = 77791709 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (77799941) 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 as a sum of consecutive naturals, namely, 38899950 + 38899951.

It is an arithmetic number, because the mean of its divisors is an integer number (38899951).

Almost surely, 2^77799901 is an apocalyptic number.

It is an amenable number.

77799901 is a deficient number, since it is larger than the sum of its proper divisors (1).

77799901 is an equidigital number, since it uses as much as digits as its factorization.

77799901 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 250047, while the sum is 49.

The square root of 77799901 is about 8820.4252165074. The cubic root of 77799901 is about 426.9001900221.

The spelling of 77799901 in words is "seventy-seven million, seven hundred ninety-nine thousand, nine hundred one".