20129189471 has 4 divisors (see below), whose sum is σ = 20139063600. Its totient is φ = 20119315344.

The previous prime is 20129189447. The next prime is 20129189489. The reversal of 20129189471 is 17498192102.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 17498192102 = 2 ⋅8749096051.

It is a cyclic number.

It is not a de Polignac number, because 20129189471 - 2⁶ = 20129189407 is a prime.

It is a super-3 number, since 3×20129189471³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20129189441) 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, 4934006 + ... + 4938083.

It is an arithmetic number, because the mean of its divisors is an integer number (5034765900).

Almost surely, 2^20129189471 is an apocalyptic number.

20129189471 is a deficient number, since it is larger than the sum of its proper divisors (9874129).

20129189471 is an equidigital number, since it uses as much as digits as its factorization.

20129189471 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9874128.

The product of its (nonzero) digits is 72576, while the sum is 44.

The spelling of 20129189471 in words is "twenty billion, one hundred twenty-nine million, one hundred eighty-nine thousand, four hundred seventy-one".