1009861 has 8 divisors (see below), whose sum is σ = 1068480. Its totient is φ = 954316.

The previous prime is 1009859. The next prime is 1009873. The reversal of 1009861 is 1689001.

It is not a de Polignac number, because 1009861 - 2¹ = 1009859 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1009061) 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, 12126 + ... + 12208.

It is an arithmetic number, because the mean of its divisors is an integer number (133560).

2^1009861 is an apocalyptic number.

It is an amenable number.

1009861 is a deficient number, since it is larger than the sum of its proper divisors (58619).

1009861 is an frugal number, since it uses more digits than its factorization.

1009861 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 152 (or 106 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 25.

The square root of 1009861 is about 1004.9184046479. The cubic root of 1009861 is about 100.3276254435.

The spelling of 1009861 in words is "one million, nine thousand, eight hundred sixty-one".