19974139 has 2 divisors, whose sum is σ = 19974140. Its totient is φ = 19974138.

The previous prime is 19974121. The next prime is 19974169. The reversal of 19974139 is 93147991.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (93147991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 19974139 - 2¹³ = 19965947 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 19974095 and 19974104.

It is not a weakly prime, because it can be changed into another prime (19974169) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9987069 + 9987070.

It is an arithmetic number, because the mean of its divisors is an integer number (9987070).

Almost surely, 2^19974139 is an apocalyptic number.

19974139 is a deficient number, since it is larger than the sum of its proper divisors (1).

19974139 is an equidigital number, since it uses as much as digits as its factorization.

19974139 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 61236, while the sum is 43.

The square root of 19974139 is about 4469.2436720322. The cubic root of 19974139 is about 271.3247152727.

The spelling of 19974139 in words is "nineteen million, nine hundred seventy-four thousand, one hundred thirty-nine".