1987578166 has 16 divisors (see below), whose sum is σ = 3555419904. Its totient is φ = 814783464.

The previous prime is 1987578157. The next prime is 1987578169. The reversal of 1987578166 is 6618757891.

It is a self number, because there is not a number n which added to its sum of digits gives 1987578166.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1987578169) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3085980 + ... + 3086623.

It is an arithmetic number, because the mean of its divisors is an integer number (222213744).

Almost surely, 2^1987578166 is an apocalyptic number.

1987578166 is a deficient number, since it is larger than the sum of its proper divisors (1567841738).

1987578166 is a wasteful number, since it uses less digits than its factorization.

1987578166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6172635.

The product of its digits is 5080320, while the sum is 58.

The square root of 1987578166 is about 44582.2629080221. The cubic root of 1987578166 is about 1257.3072092645.

The spelling of 1987578166 in words is "one billion, nine hundred eighty-seven million, five hundred seventy-eight thousand, one hundred sixty-six".