19893749 has 2 divisors, whose sum is σ = 19893750. Its totient is φ = 19893748.

The previous prime is 19893719. The next prime is 19893751. The reversal of 19893749 is 94739891.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19864849 + 28900 = 4457^2 + 170^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19893749 is a prime.

It is a super-2 number, since 2×19893749² = 791522498550002, which contains 22 as substring.

Together with 19893751, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 19893697 and 19893706.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19893719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9946874 + 9946875.

It is an arithmetic number, because the mean of its divisors is an integer number (9946875).

Almost surely, 2^19893749 is an apocalyptic number.

It is an amenable number.

19893749 is a deficient number, since it is larger than the sum of its proper divisors (1).

19893749 is an equidigital number, since it uses as much as digits as its factorization.

19893749 is an evil number, because the sum of its binary digits is even.

The product of its digits is 489888, while the sum is 50.

The square root of 19893749 is about 4460.2409127759. The cubic root of 19893749 is about 270.9602252778.

The spelling of 19893749 in words is "nineteen million, eight hundred ninety-three thousand, seven hundred forty-nine".