21033245771 has 2 divisors, whose sum is σ = 21033245772. Its totient is φ = 21033245770.

The previous prime is 21033245627. The next prime is 21033245777. The reversal of 21033245771 is 17754233012.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21033245771 - 2²² = 21029051467 is a prime.

It is not a weakly prime, because it can be changed into another prime (21033245777) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10516622885 + 10516622886.

It is an arithmetic number, because the mean of its divisors is an integer number (10516622886).

Almost surely, 2^21033245771 is an apocalyptic number.

21033245771 is a deficient number, since it is larger than the sum of its proper divisors (1).

21033245771 is an equidigital number, since it uses as much as digits as its factorization.

21033245771 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 35280, while the sum is 35.

Adding to 21033245771 its reverse (17754233012), we get a palindrome (38787478783).

The spelling of 21033245771 in words is "twenty-one billion, thirty-three million, two hundred forty-five thousand, seven hundred seventy-one".