2639551 has 4 divisors (see below), whose sum is σ = 2730600. Its totient is φ = 2548504.

The previous prime is 2639521. The next prime is 2639561. The reversal of 2639551 is 1559362.

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

It is a cyclic number.

It is not a de Polignac number, because 2639551 - 2¹⁵ = 2606783 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2639501) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45481 + ... + 45538.

It is an arithmetic number, because the mean of its divisors is an integer number (682650).

2^2639551 is an apocalyptic number.

2639551 is a deficient number, since it is larger than the sum of its proper divisors (91049).

2639551 is an equidigital number, since it uses as much as digits as its factorization.

2639551 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91048.

The product of its digits is 8100, while the sum is 31.

The square root of 2639551 is about 1624.6695048532. The cubic root of 2639551 is about 138.2006288529.

The spelling of 2639551 in words is "two million, six hundred thirty-nine thousand, five hundred fifty-one".