19981079 has 2 divisors, whose sum is σ = 19981080. Its totient is φ = 19981078.

The previous prime is 19981061. The next prime is 19981109. The reversal of 19981079 is 97018991.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19981079 - 2⁸ = 19980823 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19981979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9990539 + 9990540.

It is an arithmetic number, because the mean of its divisors is an integer number (9990540).

Almost surely, 2^19981079 is an apocalyptic number.

19981079 is a deficient number, since it is larger than the sum of its proper divisors (1).

19981079 is an equidigital number, since it uses as much as digits as its factorization.

19981079 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 40824, while the sum is 44.

The square root of 19981079 is about 4470.0200223265. The cubic root of 19981079 is about 271.3561354921.

The spelling of 19981079 in words is "nineteen million, nine hundred eighty-one thousand, seventy-nine".