1994902681 has 2 divisors, whose sum is σ = 1994902682. Its totient is φ = 1994902680.

The previous prime is 1994902667. The next prime is 1994902687. The reversal of 1994902681 is 1862094991.

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., 1911088656 + 83814025 = 43716^2 + 9155^2 .

It is a cyclic number.

It is not a de Polignac number, because 1994902681 - 2¹⁷ = 1994771609 is a prime.

It is a super-2 number, since 2×1994902681² = 7959273413321975522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (1994902687) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 997451340 + 997451341.

It is an arithmetic number, because the mean of its divisors is an integer number (997451341).

Almost surely, 2^1994902681 is an apocalyptic number.

It is an amenable number.

1994902681 is a deficient number, since it is larger than the sum of its proper divisors (1).

1994902681 is an equidigital number, since it uses as much as digits as its factorization.

1994902681 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 279936, while the sum is 49.

The square root of 1994902681 is about 44664.3334328410. Note that the first 3 decimals coincide. The cubic root of 1994902681 is about 1258.8497693513.

The spelling of 1994902681 in words is "one billion, nine hundred ninety-four million, nine hundred two thousand, six hundred eighty-one".