1905409801 has 3 divisors (see below), whose sum is σ = 1905453453. Its totient is φ = 1905366150.

The previous prime is 1905409787. The next prime is 1905409817. The reversal of 1905409801 is 1089045091.

The square root of 1905409801 is 43651.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 1905409801 - 2¹⁷ = 1905278729 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1905409841) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 21826 + ... + 65476.

It is an arithmetic number, because the mean of its divisors is an integer number (635151151).

Almost surely, 2^1905409801 is an apocalyptic number.

1905409801 is the 43651-st square number.

1905409801 is the 21826-th centered octagonal number.

It is an amenable number.

1905409801 is a deficient number, since it is larger than the sum of its proper divisors (43652).

1905409801 is an frugal number, since it uses more digits than its factorization.

1905409801 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 87302 (or 43651 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 37.

The cubic root of 1905409801 is about 1239.7367202484.

The spelling of 1905409801 in words is "one billion, nine hundred five million, four hundred nine thousand, eight hundred one".