21649409311 has 2 divisors, whose sum is σ = 21649409312. Its totient is φ = 21649409310.

The previous prime is 21649409291. The next prime is 21649409321. The reversal of 21649409311 is 11390494612.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21649409311 - 2⁵ = 21649409279 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21649409321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10824704655 + 10824704656.

It is an arithmetic number, because the mean of its divisors is an integer number (10824704656).

Almost surely, 2^21649409311 is an apocalyptic number.

21649409311 is a deficient number, since it is larger than the sum of its proper divisors (1).

21649409311 is an equidigital number, since it uses as much as digits as its factorization.

21649409311 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 46656, while the sum is 40.

The spelling of 21649409311 in words is "twenty-one billion, six hundred forty-nine million, four hundred nine thousand, three hundred eleven".