19677971 has 2 divisors, whose sum is σ = 19677972. Its totient is φ = 19677970.

The previous prime is 19677947. The next prime is 19678013. The reversal of 19677971 is 17977691.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19677971 - 2⁶ = 19677907 is a prime.

It is not a weakly prime, because it can be changed into another prime (19677071) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9838985 + 9838986.

It is an arithmetic number, because the mean of its divisors is an integer number (9838986).

Almost surely, 2^19677971 is an apocalyptic number.

19677971 is a deficient number, since it is larger than the sum of its proper divisors (1).

19677971 is an equidigital number, since it uses as much as digits as its factorization.

19677971 is an evil number, because the sum of its binary digits is even.

The product of its digits is 166698, while the sum is 47.

The square root of 19677971 is about 4435.9859107080. The cubic root of 19677971 is about 269.9770030710.

The spelling of 19677971 in words is "nineteen million, six hundred seventy-seven thousand, nine hundred seventy-one".