21425234065663 has 4 divisors (see below), whose sum is σ = 21923495323048. Its totient is φ = 20926972808280.

The previous prime is 21425234065643. The next prime is 21425234065681. The reversal of 21425234065663 is 36656043252412.

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

It is a cyclic number.

It is not a de Polignac number, because 21425234065663 - 2¹³ = 21425234057471 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21425234065643) 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, 249130628628 + ... + 249130628713.

It is an arithmetic number, because the mean of its divisors is an integer number (5480873830762).

Almost surely, 2^{21425234065663} is an apocalyptic number.

21425234065663 is a deficient number, since it is larger than the sum of its proper divisors (498261257385).

21425234065663 is an equidigital number, since it uses as much as digits as its factorization.

21425234065663 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 498261257384.

The product of its (nonzero) digits is 6220800, while the sum is 49.

The spelling of 21425234065663 in words is "twenty-one trillion, four hundred twenty-five billion, two hundred thirty-four million, sixty-five thousand, six hundred sixty-three".