6420875421953 has 4 divisors (see below), whose sum is σ = 6508832619588. Its totient is φ = 6332918224320.

The previous prime is 6420875421931. The next prime is 6420875421971. The reversal of 6420875421953 is 3591245780246.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2340447141904 + 4080428280049 = 1529852^2 + 2020007^2 .

It is a cyclic number.

It is not a de Polignac number, because 6420875421953 - 2⁶ = 6420875421889 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (6420875421253) 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, 43978598708 + ... + 43978598853.

It is an arithmetic number, because the mean of its divisors is an integer number (1627208154897).

It is a 2-persistent number, because it is pandigital, and so is 2⋅6420875421953 = 12841750843906, but 3⋅6420875421953 = 19262626265859 is not.

Almost surely, 2^{6420875421953} is an apocalyptic number.

It is an amenable number.

6420875421953 is a deficient number, since it is larger than the sum of its proper divisors (87957197635).

6420875421953 is an equidigital number, since it uses as much as digits as its factorization.

6420875421953 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87957197634.

The product of its (nonzero) digits is 14515200, while the sum is 56.

The spelling of 6420875421953 in words is "six trillion, four hundred twenty billion, eight hundred seventy-five million, four hundred twenty-one thousand, nine hundred fifty-three".