19748749 has 2 divisors, whose sum is σ = 19748750. Its totient is φ = 19748748.

The previous prime is 19748737. The next prime is 19748753. The reversal of 19748749 is 94784791.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19669225 + 79524 = 4435^2 + 282^2 .

It is an emirp because it is prime and its reverse (94784791) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19748749 - 2⁵ = 19748717 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19748759) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9874374 + 9874375.

It is an arithmetic number, because the mean of its divisors is an integer number (9874375).

Almost surely, 2^19748749 is an apocalyptic number.

It is an amenable number.

19748749 is a deficient number, since it is larger than the sum of its proper divisors (1).

19748749 is an equidigital number, since it uses as much as digits as its factorization.

19748749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 508032, while the sum is 49.

The square root of 19748749 is about 4443.9564579325. The cubic root of 19748749 is about 270.3003014465.

The spelling of 19748749 in words is "nineteen million, seven hundred forty-eight thousand, seven hundred forty-nine".