21621212230291 has 2 divisors, whose sum is σ = 21621212230292. Its totient is φ = 21621212230290.

The previous prime is 21621212230279. The next prime is 21621212230313. The reversal of 21621212230291 is 19203221212612.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21621212230291 - 2⁵ = 21621212230259 is a prime.

It is not a weakly prime, because it can be changed into another prime (21621212230991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10810606115145 + 10810606115146.

It is an arithmetic number, because the mean of its divisors is an integer number (10810606115146).

Almost surely, 2^{21621212230291} is an apocalyptic number.

21621212230291 is a deficient number, since it is larger than the sum of its proper divisors (1).

21621212230291 is an equidigital number, since it uses as much as digits as its factorization.

21621212230291 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10368, while the sum is 34.

The spelling of 21621212230291 in words is "twenty-one trillion, six hundred twenty-one billion, two hundred twelve million, two hundred thirty thousand, two hundred ninety-one".