1981529 has 12 divisors (see below), whose sum is σ = 2286000. Its totient is φ = 1703160.

The previous prime is 1981523. The next prime is 1981543. The reversal of 1981529 is 9251891.

It is not a de Polignac number, because 1981529 - 2⁴ = 1981513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1981523) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3722 + ... + 4220.

It is an arithmetic number, because the mean of its divisors is an integer number (190500).

2^1981529 is an apocalyptic number.

1981529 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

1981529 is a deficient number, since it is larger than the sum of its proper divisors (304471).

1981529 is a wasteful number, since it uses less digits than its factorization.

1981529 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 548 (or 529 counting only the distinct ones).

The product of its digits is 6480, while the sum is 35.

The square root of 1981529 is about 1407.6679295914. The cubic root of 1981529 is about 125.6030380822.

The spelling of 1981529 in words is "one million, nine hundred eighty-one thousand, five hundred twenty-nine".