20372400171645 has 16 divisors (see below), whose sum is σ = 34513242644160. Its totient is φ = 10226145968384.

The previous prime is 20372400171631. The next prime is 20372400171671. The reversal of 20372400171645 is 54617100427302.

It is a cyclic number.

It is not a de Polignac number, because 20372400171645 - 2¹⁰ = 20372400170621 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20372400171597 and 20372400171606.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 39945882435 + ... + 39945882944.

It is an arithmetic number, because the mean of its divisors is an integer number (2157077665260).

Almost surely, 2^{20372400171645} is an apocalyptic number.

It is an amenable number.

20372400171645 is a deficient number, since it is larger than the sum of its proper divisors (14140842472515).

20372400171645 is a wasteful number, since it uses less digits than its factorization.

20372400171645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79891765404.

The product of its (nonzero) digits is 282240, while the sum is 42.

Adding to 20372400171645 its reverse (54617100427302), we get a palindrome (74989500598947).

The spelling of 20372400171645 in words is "twenty trillion, three hundred seventy-two billion, four hundred million, one hundred seventy-one thousand, six hundred forty-five".