21145143425025 has 24 divisors (see below), whose sum is σ = 36165486689280. Its totient is φ = 10888533624640.

The previous prime is 21145143425023. The next prime is 21145143425069. The reversal of 21145143425025 is 52052434154112.

It is not a de Polignac number, because 21145143425025 - 2¹ = 21145143425023 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21145143425023) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4860950337 + ... + 4860954686.

It is an arithmetic number, because the mean of its divisors is an integer number (1506895278720).

Almost surely, 2^{21145143425025} is an apocalyptic number.

21145143425025 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21145143425025 is a deficient number, since it is larger than the sum of its proper divisors (15020343264255).

21145143425025 is a wasteful number, since it uses less digits than its factorization.

21145143425025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9721905065 (or 9721905060 counting only the distinct ones).

The product of its (nonzero) digits is 192000, while the sum is 39.

Adding to 21145143425025 its reverse (52052434154112), we get a palindrome (73197577579137).

The spelling of 21145143425025 in words is "twenty-one trillion, one hundred forty-five billion, one hundred forty-three million, four hundred twenty-five thousand, twenty-five".