19800139 has 2 divisors, whose sum is σ = 19800140. Its totient is φ = 19800138.

The previous prime is 19800119. The next prime is 19800161. The reversal of 19800139 is 93100891.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 19800139 - 2⁹ = 19799627 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 19800139.

It is not a weakly prime, because it can be changed into another prime (19800119) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9900069 + 9900070.

It is an arithmetic number, because the mean of its divisors is an integer number (9900070).

Almost surely, 2^19800139 is an apocalyptic number.

19800139 is a deficient number, since it is larger than the sum of its proper divisors (1).

19800139 is an equidigital number, since it uses as much as digits as its factorization.

19800139 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1944, while the sum is 31.

The square root of 19800139 is about 4449.7347111935. The cubic root of 19800139 is about 270.5345559656.

The spelling of 19800139 in words is "nineteen million, eight hundred thousand, one hundred thirty-nine".