1905618961 has 32 divisors (see below), whose sum is σ = 2099520000. Its totient is φ = 1722918912.

The previous prime is 1905618959. The next prime is 1905618997. The reversal of 1905618961 is 1698165091.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1905618961 - 2¹ = 1905618959 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1905618161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12789315 + ... + 12789463.

It is an arithmetic number, because the mean of its divisors is an integer number (65610000).

Almost surely, 2^1905618961 is an apocalyptic number.

It is an amenable number.

1905618961 is a deficient number, since it is larger than the sum of its proper divisors (193901039).

1905618961 is a wasteful number, since it uses less digits than its factorization.

1905618961 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 441.

The product of its (nonzero) digits is 116640, while the sum is 46.

The square root of 1905618961 is about 43653.3957556569. The cubic root of 1905618961 is about 1239.7820812419.

The spelling of 1905618961 in words is "one billion, nine hundred five million, six hundred eighteen thousand, nine hundred sixty-one".