21432241387 has 2 divisors, whose sum is σ = 21432241388. Its totient is φ = 21432241386.

The previous prime is 21432241351. The next prime is 21432241427. The reversal of 21432241387 is 78314223412.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21432241387 is a prime.

It is not a weakly prime, because it can be changed into another prime (21432241307) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10716120693 + 10716120694.

It is an arithmetic number, because the mean of its divisors is an integer number (10716120694).

Almost surely, 2^21432241387 is an apocalyptic number.

21432241387 is a deficient number, since it is larger than the sum of its proper divisors (1).

21432241387 is an equidigital number, since it uses as much as digits as its factorization.

21432241387 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64512, while the sum is 37.

Adding to 21432241387 its reverse (78314223412), we get a palindrome (99746464799).

The spelling of 21432241387 in words is "twenty-one billion, four hundred thirty-two million, two hundred forty-one thousand, three hundred eighty-seven".