21431614849 has 2 divisors, whose sum is σ = 21431614850. Its totient is φ = 21431614848.

The previous prime is 21431614837. The next prime is 21431614861. The reversal of 21431614849 is 94841613412.

It is a balanced prime because it is at equal distance from previous prime (21431614837) and next prime (21431614861).

It can be written as a sum of positive squares in only one way, i.e., 12447418624 + 8984196225 = 111568^2 + 94785^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21431614849 is a prime.

It is not a weakly prime, because it can be changed into another prime (21431614549) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10715807424 + 10715807425.

It is an arithmetic number, because the mean of its divisors is an integer number (10715807425).

Almost surely, 2^21431614849 is an apocalyptic number.

It is an amenable number.

21431614849 is a deficient number, since it is larger than the sum of its proper divisors (1).

21431614849 is an equidigital number, since it uses as much as digits as its factorization.

21431614849 is an evil number, because the sum of its binary digits is even.

The product of its digits is 165888, while the sum is 43.

The spelling of 21431614849 in words is "twenty-one billion, four hundred thirty-one million, six hundred fourteen thousand, eight hundred forty-nine".