3912045821 has 2 divisors, whose sum is σ = 3912045822. Its totient is φ = 3912045820.

The previous prime is 3912045769. The next prime is 3912045847. The reversal of 3912045821 is 1285402193.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 3762472921 + 149572900 = 61339^2 + 12230^2 .

It is a cyclic number.

It is not a de Polignac number, because 3912045821 - 2¹⁰ = 3912044797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3912045871) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1956022910 + 1956022911.

It is an arithmetic number, because the mean of its divisors is an integer number (1956022911).

Almost surely, 2^3912045821 is an apocalyptic number.

It is an amenable number.

3912045821 is a deficient number, since it is larger than the sum of its proper divisors (1).

3912045821 is an equidigital number, since it uses as much as digits as its factorization.

3912045821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17280, while the sum is 35.

The square root of 3912045821 is about 62546.3493818784. The cubic root of 3912045821 is about 1575.6798369891.

The spelling of 3912045821 in words is "three billion, nine hundred twelve million, forty-five thousand, eight hundred twenty-one".