1915881985 has 16 divisors (see below), whose sum is σ = 2354400576. Its totient is φ = 1495867968.

The previous prime is 1915881971. The next prime is 1915882051. The reversal of 1915881985 is 5891885191.

It is a cyclic number.

It is not a de Polignac number, because 1915881985 - 2¹⁷ = 1915750913 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 347067 + ... + 352543.

It is an arithmetic number, because the mean of its divisors is an integer number (147150036).

Almost surely, 2^1915881985 is an apocalyptic number.

It is an amenable number.

1915881985 is a deficient number, since it is larger than the sum of its proper divisors (438518591).

1915881985 is a wasteful number, since it uses less digits than its factorization.

1915881985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7152.

The product of its digits is 1036800, while the sum is 55.

The square root of 1915881985 is about 43770.7891749738. The cubic root of 1915881985 is about 1242.0037809229.

The spelling of 1915881985 in words is "one billion, nine hundred fifteen million, eight hundred eighty-one thousand, nine hundred eighty-five".