21770847893 has 2 divisors, whose sum is σ = 21770847894. Its totient is φ = 21770847892.

The previous prime is 21770847859. The next prime is 21770847911. The reversal of 21770847893 is 39874807712.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15789681649 + 5981166244 = 125657^2 + 77338^2 .

It is a cyclic number.

It is not a de Polignac number, because 21770847893 - 2⁶ = 21770847829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21770840893) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10885423946 + 10885423947.

It is an arithmetic number, because the mean of its divisors is an integer number (10885423947).

Almost surely, 2^21770847893 is an apocalyptic number.

It is an amenable number.

21770847893 is a deficient number, since it is larger than the sum of its proper divisors (1).

21770847893 is an equidigital number, since it uses as much as digits as its factorization.

21770847893 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4741632, while the sum is 56.

The spelling of 21770847893 in words is "twenty-one billion, seven hundred seventy million, eight hundred forty-seven thousand, eight hundred ninety-three".