20908186069 has 4 divisors (see below), whose sum is σ = 20921496480. Its totient is φ = 20894875660.

The previous prime is 20908186067. The next prime is 20908186147. The reversal of 20908186069 is 96068180902.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 96068180902 = 2 ⋅48034090451.

It is a cyclic number.

It is not a de Polignac number, because 20908186069 - 2¹ = 20908186067 is a prime.

It is a super-2 number, since 2×20908186069² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (49) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20908186063) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6652849 + ... + 6655990.

It is an arithmetic number, because the mean of its divisors is an integer number (5230374120).

Almost surely, 2^20908186069 is an apocalyptic number.

It is an amenable number.

20908186069 is a deficient number, since it is larger than the sum of its proper divisors (13310411).

20908186069 is a wasteful number, since it uses less digits than its factorization.

20908186069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13310410.

The product of its (nonzero) digits is 373248, while the sum is 49.

The spelling of 20908186069 in words is "twenty billion, nine hundred eight million, one hundred eighty-six thousand, sixty-nine".