19981026 has 32 divisors (see below), whose sum is σ = 47819520. Its totient is φ = 6147792.

The previous prime is 19981021. The next prime is 19981057. The reversal of 19981026 is 62018991.

It is not an unprimeable number, because it can be changed into a prime (19981021) 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 15 ways as a sum of consecutive naturals, for example, 13530 + ... + 14933.

It is an arithmetic number, because the mean of its divisors is an integer number (1494360).

Almost surely, 2^19981026 is an apocalyptic number.

19981026 is an abundant number, since it is smaller than the sum of its proper divisors (27838494).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

19981026 is a wasteful number, since it uses less digits than its factorization.

19981026 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28487 (or 28481 counting only the distinct ones).

The product of its (nonzero) digits is 7776, while the sum is 36.

The square root of 19981026 is about 4470.0140939375. The cubic root of 19981026 is about 271.3558955669.

It can be divided in two parts, 199 and 81026, that added together give a square (81225 = 285²).

The spelling of 19981026 in words is "nineteen million, nine hundred eighty-one thousand, twenty-six".