1909801 has 2 divisors, whose sum is σ = 1909802. Its totient is φ = 1909800.

The previous prime is 1909799. The next prime is 1909807. The reversal of 1909801 is 1089091.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1819801 + 90000 = 1349^2 + 300^2 .

It is an emirp because it is prime and its reverse (1089091) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1909801 - 2¹ = 1909799 is a prime.

Together with 1909799, it forms a pair of twin primes.

It is an Ulam number.

It is a self number, because there is not a number n which added to its sum of digits gives 1909801.

It is not a weakly prime, because it can be changed into another prime (1909807) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 954900 + 954901.

It is an arithmetic number, because the mean of its divisors is an integer number (954901).

2^1909801 is an apocalyptic number.

It is an amenable number.

1909801 is a deficient number, since it is larger than the sum of its proper divisors (1).

1909801 is an equidigital number, since it uses as much as digits as its factorization.

1909801 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 28.

The square root of 1909801 is about 1381.9554985599. The cubic root of 1909801 is about 124.0688353500.

The spelling of 1909801 in words is "one million, nine hundred nine thousand, eight hundred one".