21513410851 has 2 divisors, whose sum is σ = 21513410852. Its totient is φ = 21513410850.

The previous prime is 21513410833. The next prime is 21513410911. The reversal of 21513410851 is 15801431512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21513410851 - 2⁵ = 21513410819 is a prime.

It is not a weakly prime, because it can be changed into another prime (21513410651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10756705425 + 10756705426.

It is an arithmetic number, because the mean of its divisors is an integer number (10756705426).

Almost surely, 2^21513410851 is an apocalyptic number.

21513410851 is a deficient number, since it is larger than the sum of its proper divisors (1).

21513410851 is an equidigital number, since it uses as much as digits as its factorization.

21513410851 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4800, while the sum is 31.

The spelling of 21513410851 in words is "twenty-one billion, five hundred thirteen million, four hundred ten thousand, eight hundred fifty-one".