1642063921 has 2 divisors, whose sum is σ = 1642063922. Its totient is φ = 1642063920.

The previous prime is 1642063903. The next prime is 1642063937. The reversal of 1642063921 is 1293602461.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1636607025 + 5456896 = 40455^2 + 2336^2 .

It is an emirp because it is prime and its reverse (1293602461) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1642063921 - 2¹⁷ = 1641932849 is a prime.

It is not a weakly prime, because it can be changed into another prime (1642063991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 821031960 + 821031961.

It is an arithmetic number, because the mean of its divisors is an integer number (821031961).

Almost surely, 2^1642063921 is an apocalyptic number.

It is an amenable number.

1642063921 is a deficient number, since it is larger than the sum of its proper divisors (1).

1642063921 is an equidigital number, since it uses as much as digits as its factorization.

1642063921 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 15552, while the sum is 34.

The square root of 1642063921 is about 40522.3878985432. The cubic root of 1642063921 is about 1179.7682013804.

The spelling of 1642063921 in words is "one billion, six hundred forty-two million, sixty-three thousand, nine hundred twenty-one".