2551636 has 6 divisors (see below), whose sum is σ = 4465370. Its totient is φ = 1275816.

The previous prime is 2551607. The next prime is 2551639. The reversal of 2551636 is 6361552.

It can be written as a sum of positive squares in only one way, i.e., 1943236 + 608400 = 1394^2 + 780^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2551639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 318951 + ... + 318958.

2^2551636 is an apocalyptic number.

It is an amenable number.

2551636 is a deficient number, since it is larger than the sum of its proper divisors (1913734).

2551636 is a wasteful number, since it uses less digits than its factorization.

2551636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 637913 (or 637911 counting only the distinct ones).

The product of its digits is 5400, while the sum is 28.

The square root of 2551636 is about 1597.3841116025. The cubic root of 2551636 is about 136.6489315343.

It can be divided in two parts, 25516 and 36, that added together give a palindrome (25552).

The spelling of 2551636 in words is "two million, five hundred fifty-one thousand, six hundred thirty-six".