2187729 has 14 divisors (see below), whose sum is σ = 3281186. Its totient is φ = 1458000.

The previous prime is 2187727. The next prime is 2187743. The reversal of 2187729 is 9277812.

It can be written as a sum of positive squares in only one way, i.e., 1896129 + 291600 = 1377^2 + 540^2 .

It is not a de Polignac number, because 2187729 - 2¹ = 2187727 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2187693 and 2187702.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2187727) by changing a digit.

It is a polite number, since it can be written in 13 ways as a sum of consecutive naturals, for example, 772 + ... + 2229.

2^2187729 is an apocalyptic number.

It is an amenable number.

2187729 is a deficient number, since it is larger than the sum of its proper divisors (1093457).

2187729 is an frugal number, since it uses more digits than its factorization.

2187729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3019 (or 3004 counting only the distinct ones).

The product of its digits is 14112, while the sum is 36.

The square root of 2187729 is about 1479.0973598787. The cubic root of 2187729 is about 129.8168822212.

It can be divided in two parts, 2187 and 729, that multiplied together give a 13-th power (1594323 = 3¹³).

The spelling of 2187729 in words is "two million, one hundred eighty-seven thousand, seven hundred twenty-nine".