21399526329523 has 2 divisors, whose sum is σ = 21399526329524. Its totient is φ = 21399526329522.

The previous prime is 21399526329449. The next prime is 21399526329529. The reversal of 21399526329523 is 32592362599312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21399526329523 - 2²¹ = 21399524232371 is a prime.

It is not a weakly prime, because it can be changed into another prime (21399526329529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10699763164761 + 10699763164762.

It is an arithmetic number, because the mean of its divisors is an integer number (10699763164762).

Almost surely, 2^{21399526329523} is an apocalyptic number.

21399526329523 is a deficient number, since it is larger than the sum of its proper divisors (1).

21399526329523 is an equidigital number, since it uses as much as digits as its factorization.

21399526329523 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 47239200, while the sum is 61.

The spelling of 21399526329523 in words is "twenty-one trillion, three hundred ninety-nine billion, five hundred twenty-six million, three hundred twenty-nine thousand, five hundred twenty-three".