2631609 has 20 divisors (see below), whose sum is σ = 4011876. Its totient is φ = 1718496.

The previous prime is 2631581. The next prime is 2631631. The reversal of 2631609 is 9061362.

It is a happy number.

2631609 is a `hidden beast` number, since 26 + 31 + 609 = 666.

2631609 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 685584 + 1946025 = 828^2 + 1395^2 .

It is not a de Polignac number, because 2631609 - 2¹⁶ = 2566073 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

2631609 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (2631649) 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 19 ways as a sum of consecutive naturals, for example, 3987 + ... + 4599.

2^2631609 is an apocalyptic number.

It is an amenable number.

2631609 is a deficient number, since it is larger than the sum of its proper divisors (1380267).

2631609 is an equidigital number, since it uses as much as digits as its factorization.

2631609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 678 (or 669 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 27.

The square root of 2631609 is about 1622.2234741243. The cubic root of 2631609 is about 138.0618815099.

It can be divided in two parts, 263160 and 9, that added together give a square (263169 = 513²).

The spelling of 2631609 in words is "two million, six hundred thirty-one thousand, six hundred nine".