21212025541 has 16 divisors (see below), whose sum is σ = 24727223808. Its totient is φ = 17818819200.

The previous prime is 21212025481. The next prime is 21212025577. The reversal of 21212025541 is 14552021212.

It is not a de Polignac number, because 21212025541 - 2⁷ = 21212025413 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21212025041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 306601 + ... + 369361.

It is an arithmetic number, because the mean of its divisors is an integer number (1545451488).

Almost surely, 2^21212025541 is an apocalyptic number.

It is an amenable number.

21212025541 is a deficient number, since it is larger than the sum of its proper divisors (3515198267).

21212025541 is an equidigital number, since it uses as much as digits as its factorization.

21212025541 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 63732.

The product of its (nonzero) digits is 1600, while the sum is 25.

Adding to 21212025541 its reverse (14552021212), we get a palindrome (35764046753).

The spelling of 21212025541 in words is "twenty-one billion, two hundred twelve million, twenty-five thousand, five hundred forty-one".