3861394021 has 2 divisors, whose sum is σ = 3861394022. Its totient is φ = 3861394020.

The previous prime is 3861393989. The next prime is 3861394091. The reversal of 3861394021 is 1204931683.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 3824061921 + 37332100 = 61839^2 + 6110^2 .

It is a cyclic number.

It is not a de Polignac number, because 3861394021 - 2⁵ = 3861393989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3861394091) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1930697010 + 1930697011.

It is an arithmetic number, because the mean of its divisors is an integer number (1930697011).

Almost surely, 2^3861394021 is an apocalyptic number.

It is an amenable number.

3861394021 is a deficient number, since it is larger than the sum of its proper divisors (1).

3861394021 is an equidigital number, since it uses as much as digits as its factorization.

3861394021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 31104, while the sum is 37.

The square root of 3861394021 is about 62140.1160362611. The cubic root of 3861394021 is about 1568.8498237436.

The spelling of 3861394021 in words is "three billion, eight hundred sixty-one million, three hundred ninety-four thousand, twenty-one".