19870780877 has 2 divisors, whose sum is σ = 19870780878. Its totient is φ = 19870780876.

The previous prime is 19870780859. The next prime is 19870780907. The reversal of 19870780877 is 77808707891.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12521833801 + 7348947076 = 111901^2 + 85726^2 .

It is a cyclic number.

It is not a de Polignac number, because 19870780877 - 2²⁰ = 19869732301 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19870780277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9935390438 + 9935390439.

It is an arithmetic number, because the mean of its divisors is an integer number (9935390439).

Almost surely, 2^19870780877 is an apocalyptic number.

It is an amenable number.

19870780877 is a deficient number, since it is larger than the sum of its proper divisors (1).

19870780877 is an equidigital number, since it uses as much as digits as its factorization.

19870780877 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11063808, while the sum is 62.

The spelling of 19870780877 in words is "nineteen billion, eight hundred seventy million, seven hundred eighty thousand, eight hundred seventy-seven".