21771415733 has 2 divisors, whose sum is σ = 21771415734. Its totient is φ = 21771415732.

The previous prime is 21771415697. The next prime is 21771415751. The reversal of 21771415733 is 33751417712.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21229364209 + 542051524 = 145703^2 + 23282^2 .

It is a cyclic number.

It is not a de Polignac number, because 21771415733 - 2¹² = 21771411637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21771415763) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10885707866 + 10885707867.

It is an arithmetic number, because the mean of its divisors is an integer number (10885707867).

Almost surely, 2^21771415733 is an apocalyptic number.

It is an amenable number.

21771415733 is a deficient number, since it is larger than the sum of its proper divisors (1).

21771415733 is an equidigital number, since it uses as much as digits as its factorization.

21771415733 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 123480, while the sum is 41.

The spelling of 21771415733 in words is "twenty-one billion, seven hundred seventy-one million, four hundred fifteen thousand, seven hundred thirty-three".