1987383857 has 16 divisors (see below), whose sum is σ = 2056646592. Its totient is φ = 1919220480.

The previous prime is 1987383823. The next prime is 1987383887. The reversal of 1987383857 is 7583837891.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1987383857 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1987383796 and 1987383805.

It is not an unprimeable number, because it can be changed into a prime (1987383887) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2318573 + ... + 2319429.

It is an arithmetic number, because the mean of its divisors is an integer number (128540412).

Almost surely, 2^1987383857 is an apocalyptic number.

It is an amenable number.

1987383857 is a deficient number, since it is larger than the sum of its proper divisors (69262735).

1987383857 is a wasteful number, since it uses less digits than its factorization.

1987383857 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1408.

The product of its digits is 10160640, while the sum is 59.

The square root of 1987383857 is about 44580.0836360813. The cubic root of 1987383857 is about 1257.2662357701.

The spelling of 1987383857 in words is "one billion, nine hundred eighty-seven million, three hundred eighty-three thousand, eight hundred fifty-seven".