3921997 has 2 divisors, whose sum is σ = 3921998. Its totient is φ = 3921996.

The previous prime is 3921991. The next prime is 3922003. The reversal of 3921997 is 7991293.

It is a balanced prime because it is at equal distance from previous prime (3921991) and next prime (3922003).

It can be written as a sum of positive squares in only one way, i.e., 3709476 + 212521 = 1926^2 + 461^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-3921997 is a prime.

It is a nialpdrome in base 13.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3921991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1960998 + 1960999.

It is an arithmetic number, because the mean of its divisors is an integer number (1960999).

Almost surely, 2^3921997 is an apocalyptic number.

It is an amenable number.

3921997 is a deficient number, since it is larger than the sum of its proper divisors (1).

3921997 is an equidigital number, since it uses as much as digits as its factorization.

3921997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 30618, while the sum is 40.

The square root of 3921997 is about 1980.4032417667. The cubic root of 3921997 is about 157.7014739192.

The spelling of 3921997 in words is "three million, nine hundred twenty-one thousand, nine hundred ninety-seven".