2621009 has 8 divisors (see below), whose sum is σ = 2828520. Its totient is φ = 2419456.

The previous prime is 2620999. The next prime is 2621023. The reversal of 2621009 is 9001262.

It can be written as a sum of positive squares in 4 ways, for example, as 1507984 + 1113025 = 1228^2 + 1055^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 2621009 - 2²⁰ = 1572433 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2621309) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 554 + ... + 2355.

It is an arithmetic number, because the mean of its divisors is an integer number (353565).

2^2621009 is an apocalyptic number.

It is an amenable number.

2621009 is a deficient number, since it is larger than the sum of its proper divisors (207511).

2621009 is a wasteful number, since it uses less digits than its factorization.

2621009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2979.

The product of its (nonzero) digits is 216, while the sum is 20.

The square root of 2621009 is about 1618.9530567623. The cubic root of 2621009 is about 137.8762630962.

The spelling of 2621009 in words is "two million, six hundred twenty-one thousand, nine".