19742791 has 2 divisors, whose sum is σ = 19742792. Its totient is φ = 19742790.

The previous prime is 19742761. The next prime is 19742803. The reversal of 19742791 is 19724791.

It is a strong prime.

It is an emirp because it is prime and its reverse (19724791) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19742791 - 2⁵ = 19742759 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19742741) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9871395 + 9871396.

It is an arithmetic number, because the mean of its divisors is an integer number (9871396).

Almost surely, 2^19742791 is an apocalyptic number.

19742791 is a deficient number, since it is larger than the sum of its proper divisors (1).

19742791 is an equidigital number, since it uses as much as digits as its factorization.

19742791 is an evil number, because the sum of its binary digits is even.

The product of its digits is 31752, while the sum is 40.

The square root of 19742791 is about 4443.2860587633. The cubic root of 19742791 is about 270.2731164135.

The spelling of 19742791 in words is "nineteen million, seven hundred forty-two thousand, seven hundred ninety-one".