21451430087 has 2 divisors, whose sum is σ = 21451430088. Its totient is φ = 21451430086.

The previous prime is 21451430047. The next prime is 21451430089. The reversal of 21451430087 is 78003415412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21451430087 - 2¹⁶ = 21451364551 is a prime.

Together with 21451430089, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21451430089) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10725715043 + 10725715044.

It is an arithmetic number, because the mean of its divisors is an integer number (10725715044).

Almost surely, 2^21451430087 is an apocalyptic number.

21451430087 is a deficient number, since it is larger than the sum of its proper divisors (1).

21451430087 is an equidigital number, since it uses as much as digits as its factorization.

21451430087 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 26880, while the sum is 35.

Adding to 21451430087 its reverse (78003415412), we get a palindrome (99454845499).

The spelling of 21451430087 in words is "twenty-one billion, four hundred fifty-one million, four hundred thirty thousand, eighty-seven".