21653513351 has 2 divisors, whose sum is σ = 21653513352. Its totient is φ = 21653513350.

The previous prime is 21653513347. The next prime is 21653513353. The reversal of 21653513351 is 15331535612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21653513351 - 2² = 21653513347 is a prime.

Together with 21653513353, 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 (21653513353) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10826756675 + 10826756676.

It is an arithmetic number, because the mean of its divisors is an integer number (10826756676).

Almost surely, 2^21653513351 is an apocalyptic number.

21653513351 is a deficient number, since it is larger than the sum of its proper divisors (1).

21653513351 is an equidigital number, since it uses as much as digits as its factorization.

21653513351 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 40500, while the sum is 35.

The spelling of 21653513351 in words is "twenty-one billion, six hundred fifty-three million, five hundred thirteen thousand, three hundred fifty-one".