3654491821 has 2 divisors, whose sum is σ = 3654491822. Its totient is φ = 3654491820.

The previous prime is 3654491807. The next prime is 3654491831. The reversal of 3654491821 is 1281944563.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 2767286025 + 887205796 = 52605^2 + 29786^2 .

It is a cyclic number.

It is not a de Polignac number, because 3654491821 - 2¹⁹ = 3653967533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3654491831) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1827245910 + 1827245911.

It is an arithmetic number, because the mean of its divisors is an integer number (1827245911).

Almost surely, 2^3654491821 is an apocalyptic number.

It is an amenable number.

3654491821 is a deficient number, since it is larger than the sum of its proper divisors (1).

3654491821 is an equidigital number, since it uses as much as digits as its factorization.

3654491821 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 207360, while the sum is 43.

The square root of 3654491821 is about 60452.3930130148. The cubic root of 3654491821 is about 1540.3130612491.

The spelling of 3654491821 in words is "three billion, six hundred fifty-four million, four hundred ninety-one thousand, eight hundred twenty-one".