1973509 has 2 divisors, whose sum is σ = 1973510. Its totient is φ = 1973508.

The previous prime is 1973507. The next prime is 1973519. The reversal of 1973509 is 9053791.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1216609 + 756900 = 1103^2 + 870^2 .

It is an emirp because it is prime and its reverse (9053791) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1973509 - 2¹ = 1973507 is a prime.

Together with 1973507, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1973501) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 986754 + 986755.

It is an arithmetic number, because the mean of its divisors is an integer number (986755).

2^1973509 is an apocalyptic number.

It is an amenable number.

1973509 is a deficient number, since it is larger than the sum of its proper divisors (1).

1973509 is an equidigital number, since it uses as much as digits as its factorization.

1973509 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8505, while the sum is 34.

The square root of 1973509 is about 1404.8163581052. The cubic root of 1973509 is about 125.4333545611.

The spelling of 1973509 in words is "one million, nine hundred seventy-three thousand, five hundred nine".