21431430461 has 8 divisors (see below), whose sum is σ = 24534793920. Its totient is φ = 18338499648.

The previous prime is 21431430403. The next prime is 21431430491. The reversal of 21431430461 is 16403413412.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21431430461 - 2²⁶ = 21364321597 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21431430401) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2603756 + ... + 2611973.

It is an arithmetic number, because the mean of its divisors is an integer number (3066849240).

Almost surely, 2^21431430461 is an apocalyptic number.

It is an amenable number.

21431430461 is a deficient number, since it is larger than the sum of its proper divisors (3103363459).

21431430461 is an equidigital number, since it uses as much as digits as its factorization.

21431430461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5216323.

The product of its (nonzero) digits is 6912, while the sum is 29.

Adding to 21431430461 its reverse (16403413412), we get a palindrome (37834843873).

The spelling of 21431430461 in words is "twenty-one billion, four hundred thirty-one million, four hundred thirty thousand, four hundred sixty-one".