20494568749 has 2 divisors, whose sum is σ = 20494568750. Its totient is φ = 20494568748.

The previous prime is 20494568729. The next prime is 20494568767. The reversal of 20494568749 is 94786549402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15430111524 + 5064457225 = 124218^2 + 71165^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20494568749 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20494568693 and 20494568702.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20494568719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10247284374 + 10247284375.

It is an arithmetic number, because the mean of its divisors is an integer number (10247284375).

Almost surely, 2^20494568749 is an apocalyptic number.

It is an amenable number.

20494568749 is a deficient number, since it is larger than the sum of its proper divisors (1).

20494568749 is an equidigital number, since it uses as much as digits as its factorization.

20494568749 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 17418240, while the sum is 58.

The spelling of 20494568749 in words is "twenty billion, four hundred ninety-four million, five hundred sixty-eight thousand, seven hundred forty-nine".