19780129 has 8 divisors (see below), whose sum is σ = 21431520. Its totient is φ = 18182976.

The previous prime is 19780109. The next prime is 19780141. The reversal of 19780129 is 92108791.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 19780129 - 2¹¹ = 19778081 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19780109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12799 + ... + 14260.

It is an arithmetic number, because the mean of its divisors is an integer number (2678940).

Almost surely, 2^19780129 is an apocalyptic number.

It is an amenable number.

19780129 is a deficient number, since it is larger than the sum of its proper divisors (1651391).

19780129 is a wasteful number, since it uses less digits than its factorization.

19780129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27119.

The product of its (nonzero) digits is 9072, while the sum is 37.

The square root of 19780129 is about 4447.4856941872. The cubic root of 19780129 is about 270.4433912676.

The spelling of 19780129 in words is "nineteen million, seven hundred eighty thousand, one hundred twenty-nine".