19713731 has 2 divisors, whose sum is σ = 19713732. Its totient is φ = 19713730.

The previous prime is 19713719. The next prime is 19713763. The reversal of 19713731 is 13731791.

It is an a-pointer prime, because the next prime (19713763) can be obtained adding 19713731 to its sum of digits (32).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19713731 - 2⁶ = 19713667 is a prime.

It is a super-2 number, since 2×19713731² = 777262379880722, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (19713131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9856865 + 9856866.

It is an arithmetic number, because the mean of its divisors is an integer number (9856866).

Almost surely, 2^19713731 is an apocalyptic number.

19713731 is a deficient number, since it is larger than the sum of its proper divisors (1).

19713731 is an equidigital number, since it uses as much as digits as its factorization.

19713731 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3969, while the sum is 32.

The square root of 19713731 is about 4440.0147522277. The cubic root of 19713731 is about 270.1404436235.

The spelling of 19713731 in words is "nineteen million, seven hundred thirteen thousand, seven hundred thirty-one".