20171391009 has 48 divisors (see below), whose sum is σ = 34156059840. Its totient is φ = 10470781440.

The previous prime is 20171390971. The next prime is 20171391017. The reversal of 20171391009 is 90019317102.

It is not a de Polignac number, because 20171391009 - 2¹² = 20171386913 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (20171390009) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2597877 + ... + 2605629.

It is an arithmetic number, because the mean of its divisors is an integer number (711584580).

Almost surely, 2^20171391009 is an apocalyptic number.

It is an amenable number.

20171391009 is a deficient number, since it is larger than the sum of its proper divisors (13984668831).

20171391009 is a wasteful number, since it uses less digits than its factorization.

20171391009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9390 (or 9383 counting only the distinct ones).

The product of its (nonzero) digits is 3402, while the sum is 33.

The spelling of 20171391009 in words is "twenty billion, one hundred seventy-one million, three hundred ninety-one thousand, nine".