1939621 has 2 divisors, whose sum is σ = 1939622. Its totient is φ = 1939620.

The previous prime is 1939603. The next prime is 1939631. The reversal of 1939621 is 1269391.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1718721 + 220900 = 1311^2 + 470^2 .

It is an emirp because it is prime and its reverse (1269391) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1939621 - 2⁷ = 1939493 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1939631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 969810 + 969811.

It is an arithmetic number, because the mean of its divisors is an integer number (969811).

2^1939621 is an apocalyptic number.

It is an amenable number.

1939621 is a deficient number, since it is larger than the sum of its proper divisors (1).

1939621 is an equidigital number, since it uses as much as digits as its factorization.

1939621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2916, while the sum is 31.

The square root of 1939621 is about 1392.7027680018. The cubic root of 1939621 is about 124.7112481593.

The spelling of 1939621 in words is "one million, nine hundred thirty-nine thousand, six hundred twenty-one".