19801005 has 32 divisors (see below), whose sum is σ = 38340864. Its totient is φ = 8518656.

The previous prime is 19801003. The next prime is 19801009. The reversal of 19801005 is 50010891.

It is not a de Polignac number, because 19801005 - 2¹ = 19801003 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19801003) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 3762 + ... + 7331.

It is an arithmetic number, because the mean of its divisors is an integer number (1198152).

Almost surely, 2^19801005 is an apocalyptic number.

19801005 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

19801005 is a deficient number, since it is larger than the sum of its proper divisors (18539859).

19801005 is a wasteful number, since it uses less digits than its factorization.

19801005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11125.

The product of its (nonzero) digits is 360, while the sum is 24.

The square root of 19801005 is about 4449.8320193014. The cubic root of 19801005 is about 270.5385000374.

Adding to 19801005 its reverse (50010891), we get a palindrome (69811896).

The spelling of 19801005 in words is "nineteen million, eight hundred one thousand, five".