20320420121545 has 8 divisors (see below), whose sum is σ = 24384924388296. Its totient is φ = 16256055935616.

The previous prime is 20320420121501. The next prime is 20320420121591. The reversal of 20320420121545 is 54512102402302.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 2787751158336 + 17532668963209 = 1669656^2 + 4187203^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20320420121545 - 2²³ = 20320411732937 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 34700802 + ... + 35281531.

It is an arithmetic number, because the mean of its divisors is an integer number (3048115548537).

Almost surely, 2^{20320420121545} is an apocalyptic number.

It is an amenable number.

20320420121545 is a deficient number, since it is larger than the sum of its proper divisors (4064504266751).

20320420121545 is an equidigital number, since it uses as much as digits as its factorization.

20320420121545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70040411.

The product of its (nonzero) digits is 19200, while the sum is 31.

Adding to 20320420121545 its reverse (54512102402302), we get a palindrome (74832522523847).

The spelling of 20320420121545 in words is "twenty trillion, three hundred twenty billion, four hundred twenty million, one hundred twenty-one thousand, five hundred forty-five".