21234425461 has 4 divisors (see below), whose sum is σ = 21635075052. Its totient is φ = 20833775872.

The previous prime is 21234425437. The next prime is 21234425483. The reversal of 21234425461 is 16452443212.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 15801998436 + 5432427025 = 125706^2 + 73705^2 .

It is a cyclic number.

It is not a de Polignac number, because 21234425461 - 2¹⁹ = 21233901173 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21234425411) 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, 200324716 + ... + 200324821.

It is an arithmetic number, because the mean of its divisors is an integer number (5408768763).

Almost surely, 2^21234425461 is an apocalyptic number.

It is an amenable number.

21234425461 is a deficient number, since it is larger than the sum of its proper divisors (400649591).

21234425461 is an equidigital number, since it uses as much as digits as its factorization.

21234425461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 400649590.

The product of its digits is 46080, while the sum is 34.

Adding to 21234425461 its reverse (16452443212), we get a palindrome (37686868673).

The spelling of 21234425461 in words is "twenty-one billion, two hundred thirty-four million, four hundred twenty-five thousand, four hundred sixty-one".