1985815605 has 8 divisors (see below), whose sum is σ = 3177304992. Its totient is φ = 1059101648.

The previous prime is 1985815603. The next prime is 1985815631. The reversal of 1985815605 is 5065185891.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1985815605 - 2¹ = 1985815603 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1985815603) 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, 66193839 + ... + 66193868.

It is an arithmetic number, because the mean of its divisors is an integer number (397163124).

Almost surely, 2^1985815605 is an apocalyptic number.

1985815605 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1985815605 is a deficient number, since it is larger than the sum of its proper divisors (1191489387).

1985815605 is a wasteful number, since it uses less digits than its factorization.

1985815605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 132387715.

The product of its (nonzero) digits is 432000, while the sum is 48.

The square root of 1985815605 is about 44562.4910098168. The cubic root of 1985815605 is about 1256.9354442562.

The spelling of 1985815605 in words is "one billion, nine hundred eighty-five million, eight hundred fifteen thousand, six hundred five".