2638945 has 4 divisors (see below), whose sum is σ = 3166740. Its totient is φ = 2111152.

The previous prime is 2638931. The next prime is 2638949. The reversal of 2638945 is 5498362.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1272384 + 1366561 = 1128^2 + 1169^2 .

It is a cyclic number.

It is not a de Polignac number, because 2638945 - 2¹¹ = 2636897 is a prime.

It is a d-powerful number, because it can be written as 2²¹ + 6⁷ + 3¹¹ + 8 + 9⁴ + 4² + 5⁷ .

It is not an unprimeable number, because it can be changed into a prime (2638949) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 263890 + ... + 263899.

It is an arithmetic number, because the mean of its divisors is an integer number (791685).

2^2638945 is an apocalyptic number.

It is an amenable number.

2638945 is a deficient number, since it is larger than the sum of its proper divisors (527795).

2638945 is an equidigital number, since it uses as much as digits as its factorization.

2638945 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 527794.

The product of its digits is 51840, while the sum is 37.

The square root of 2638945 is about 1624.4829946786. The cubic root of 2638945 is about 138.1900518026.

The spelling of 2638945 in words is "two million, six hundred thirty-eight thousand, nine hundred forty-five".