21601630674391 has 2 divisors, whose sum is σ = 21601630674392. Its totient is φ = 21601630674390.

The previous prime is 21601630674307. The next prime is 21601630674439. The reversal of 21601630674391 is 19347603610612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21601630674391 - 2⁷ = 21601630674263 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21601630678391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10800815337195 + 10800815337196.

It is an arithmetic number, because the mean of its divisors is an integer number (10800815337196).

Almost surely, 2^{21601630674391} is an apocalyptic number.

21601630674391 is a deficient number, since it is larger than the sum of its proper divisors (1).

21601630674391 is an equidigital number, since it uses as much as digits as its factorization.

21601630674391 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 979776, while the sum is 49.

The spelling of 21601630674391 in words is "twenty-one trillion, six hundred one billion, six hundred thirty million, six hundred seventy-four thousand, three hundred ninety-one".