309887387123 has 4 divisors (see below), whose sum is σ = 311509834368. Its totient is φ = 308264939880.

The previous prime is 309887387113. The next prime is 309887387141. The reversal of 309887387123 is 321783788903.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 321783788903 = 93139 ⋅3454877.

It is a cyclic number.

It is not a de Polignac number, because 309887387123 - 2²⁰ = 309886338547 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (309887387113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 811223336 + ... + 811223717.

It is an arithmetic number, because the mean of its divisors is an integer number (77877458592).

Almost surely, 2^309887387123 is an apocalyptic number.

309887387123 is a deficient number, since it is larger than the sum of its proper divisors (1622447245).

309887387123 is a wasteful number, since it uses less digits than its factorization.

309887387123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1622447244.

The product of its (nonzero) digits is 12192768, while the sum is 59.

The spelling of 309887387123 in words is "three hundred nine billion, eight hundred eighty-seven million, three hundred eighty-seven thousand, one hundred twenty-three".