1985405 has 8 divisors (see below), whose sum is σ = 2508000. Its totient is φ = 1504656.

The previous prime is 1985377. The next prime is 1985407. The reversal of 1985405 is 5045891.

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 1985405 - 2¹⁴ = 1969021 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1985407) 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, 10355 + ... + 10544.

It is an arithmetic number, because the mean of its divisors is an integer number (313500).

2^1985405 is an apocalyptic number.

It is an amenable number.

1985405 is a deficient number, since it is larger than the sum of its proper divisors (522595).

1985405 is a wasteful number, since it uses less digits than its factorization.

1985405 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20923.

The product of its (nonzero) digits is 7200, while the sum is 32.

The square root of 1985405 is about 1409.0440021518. The cubic root of 1985405 is about 125.6848806546.

The spelling of 1985405 in words is "one million, nine hundred eighty-five thousand, four hundred five".