21511425025353 has 4 divisors (see below), whose sum is σ = 28681900033808. Its totient is φ = 14340950016900.

The previous prime is 21511425025283. The next prime is 21511425025361. The reversal of 21511425025353 is 35352052411512.

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 not a de Polignac number, because 21511425025353 - 2¹⁸ = 21511424763209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21511425525353) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3585237504223 + ... + 3585237504228.

It is an arithmetic number, because the mean of its divisors is an integer number (7170475008452).

Almost surely, 2^{21511425025353} is an apocalyptic number.

It is an amenable number.

21511425025353 is a deficient number, since it is larger than the sum of its proper divisors (7170475008455).

21511425025353 is an equidigital number, since it uses as much as digits as its factorization.

21511425025353 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7170475008454.

The product of its (nonzero) digits is 180000, while the sum is 39.

Adding to 21511425025353 its reverse (35352052411512), we get a palindrome (56863477436865).

The spelling of 21511425025353 in words is "twenty-one trillion, five hundred eleven billion, four hundred twenty-five million, twenty-five thousand, three hundred fifty-three".