21214125425 has 6 divisors (see below), whose sum is σ = 26305515558. Its totient is φ = 16971300320.

The previous prime is 21214125421. The next prime is 21214125431. The reversal of 21214125425 is 52452141212.

It can be written as a sum of positive squares in 3 ways, for example, as 581388544 + 20632736881 = 24112^2 + 143641^2 .

It is not a de Polignac number, because 21214125425 - 2² = 21214125421 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21214125421) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 424282484 + ... + 424282533.

It is an arithmetic number, because the mean of its divisors is an integer number (4384252593).

Almost surely, 2^21214125425 is an apocalyptic number.

21214125425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21214125425 is a deficient number, since it is larger than the sum of its proper divisors (5091390133).

21214125425 is an equidigital number, since it uses as much as digits as its factorization.

21214125425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 848565027 (or 848565022 counting only the distinct ones).

The product of its digits is 6400, while the sum is 29.

Adding to 21214125425 its reverse (52452141212), we get a palindrome (73666266637).

The spelling of 21214125425 in words is "twenty-one billion, two hundred fourteen million, one hundred twenty-five thousand, four hundred twenty-five".