1993094021 has 2 divisors, whose sum is σ = 1993094022. Its totient is φ = 1993094020.

The previous prime is 1993093997. The next prime is 1993094057. The reversal of 1993094021 is 1204903991.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1851150625 + 141943396 = 43025^2 + 11914^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1993094021 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1993094821) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 996547010 + 996547011.

It is an arithmetic number, because the mean of its divisors is an integer number (996547011).

Almost surely, 2^1993094021 is an apocalyptic number.

It is an amenable number.

1993094021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1993094021 is an equidigital number, since it uses as much as digits as its factorization.

1993094021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17496, while the sum is 38.

The square root of 1993094021 is about 44644.0815898367. The cubic root of 1993094021 is about 1258.4692128323.

The spelling of 1993094021 in words is "one billion, nine hundred ninety-three million, ninety-four thousand, twenty-one".