21425355171601 has 4 divisors (see below), whose sum is σ = 21425391434304. Its totient is φ = 21425318908900.

The previous prime is 21425355171593. The next prime is 21425355171607. The reversal of 21425355171601 is 10617155352412.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21425355171601 - 2³ = 21425355171593 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21425355171607) 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, 17230165 + ... + 18431746.

It is an arithmetic number, because the mean of its divisors is an integer number (5356347858576).

Almost surely, 2^{21425355171601} is an apocalyptic number.

It is an amenable number.

21425355171601 is a deficient number, since it is larger than the sum of its proper divisors (36262703).

21425355171601 is an equidigital number, since it uses as much as digits as its factorization.

21425355171601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36262702.

The product of its (nonzero) digits is 252000, while the sum is 43.

The spelling of 21425355171601 in words is "twenty-one trillion, four hundred twenty-five billion, three hundred fifty-five million, one hundred seventy-one thousand, six hundred one".