309009973 has 2 divisors, whose sum is σ = 309009974. Its totient is φ = 309009972.

The previous prime is 309009971. The next prime is 309010033. The reversal of 309009973 is 379900903.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 231252849 + 77757124 = 15207^2 + 8818^2 .

It is a cyclic number.

It is not a de Polignac number, because 309009973 - 2¹ = 309009971 is a prime.

Together with 309009971, 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 (309009971) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 154504986 + 154504987.

It is an arithmetic number, because the mean of its divisors is an integer number (154504987).

Almost surely, 2^309009973 is an apocalyptic number.

It is an amenable number.

309009973 is a deficient number, since it is larger than the sum of its proper divisors (1).

309009973 is an equidigital number, since it uses as much as digits as its factorization.

309009973 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 45927, while the sum is 40.

The square root of 309009973 is about 17578.6795010319. The cubic root of 309009973 is about 676.0687034091.

The spelling of 309009973 in words is "three hundred nine million, nine thousand, nine hundred seventy-three".