3775881721 has 2 divisors, whose sum is σ = 3775881722. Its totient is φ = 3775881720.

The previous prime is 3775881619. The next prime is 3775881731. The reversal of 3775881721 is 1271885773.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2116460025 + 1659421696 = 46005^2 + 40736^2 .

It is a cyclic number.

It is not a de Polignac number, because 3775881721 - 2⁹ = 3775881209 is a prime.

It is not a weakly prime, because it can be changed into another prime (3775881731) 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, 1887940860 + 1887940861.

It is an arithmetic number, because the mean of its divisors is an integer number (1887940861).

Almost surely, 2^3775881721 is an apocalyptic number.

It is an amenable number.

3775881721 is a deficient number, since it is larger than the sum of its proper divisors (1).

3775881721 is an equidigital number, since it uses as much as digits as its factorization.

3775881721 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 658560, while the sum is 49.

The square root of 3775881721 is about 61448.2035620245. The cubic root of 3775881721 is about 1557.1823070085.

The spelling of 3775881721 in words is "three billion, seven hundred seventy-five million, eight hundred eighty-one thousand, seven hundred twenty-one".