1987780773 has 32 divisors (see below), whose sum is σ = 3029824512. Its totient is φ = 1147449600.

The previous prime is 1987780763. The next prime is 1987780867. The reversal of 1987780773 is 3770877891.

It is not a de Polignac number, because 1987780773 - 2⁴ = 1987780757 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1987780733) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 177486 + ... + 188352.

It is an arithmetic number, because the mean of its divisors is an integer number (94682016).

Almost surely, 2^1987780773 is an apocalyptic number.

It is an amenable number.

1987780773 is a deficient number, since it is larger than the sum of its proper divisors (1042043739).

1987780773 is a wasteful number, since it uses less digits than its factorization.

1987780773 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11145.

The product of its (nonzero) digits is 4148928, while the sum is 57.

The square root of 1987780773 is about 44584.5351327117. The cubic root of 1987780773 is about 1257.3499296953.

The spelling of 1987780773 in words is "one billion, nine hundred eighty-seven million, seven hundred eighty thousand, seven hundred seventy-three".