78488745977 has 2 divisors, whose sum is σ = 78488745978. Its totient is φ = 78488745976.

The previous prime is 78488745967. The next prime is 78488746009. The reversal of 78488745977 is 77954788487.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 44516358121 + 33972387856 = 210989^2 + 184316^2 .

It is a cyclic number.

It is not a de Polignac number, because 78488745977 - 2¹⁶ = 78488680441 is a prime.

It is not a weakly prime, because it can be changed into another prime (78488745967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39244372988 + 39244372989.

It is an arithmetic number, because the mean of its divisors is an integer number (39244372989).

Almost surely, 2^78488745977 is an apocalyptic number.

It is an amenable number.

78488745977 is a deficient number, since it is larger than the sum of its proper divisors (1).

78488745977 is an equidigital number, since it uses as much as digits as its factorization.

78488745977 is an evil number, because the sum of its binary digits is even.

The product of its digits is 885104640, while the sum is 74.

The spelling of 78488745977 in words is "seventy-eight billion, four hundred eighty-eight million, seven hundred forty-five thousand, nine hundred seventy-seven".