27997644 has 48 divisors (see below), whose sum is σ = 69189120. Its totient is φ = 8796480.

The previous prime is 27997639. The next prime is 27997649. The reversal of 27997644 is 44679972.

It is an interprime number because it is at equal distance from previous prime (27997639) and next prime (27997649).

It is a junction number, because it is equal to n+sod(n) for n = 27997593 and 27997602.

It is not an unprimeable number, because it can be changed into a prime (27997649) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14029 + ... + 15899.

It is an arithmetic number, because the mean of its divisors is an integer number (1441440).

Almost surely, 2^27997644 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 27997644, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34594560).

27997644 is an abundant number, since it is smaller than the sum of its proper divisors (41191476).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

27997644 is a wasteful number, since it uses less digits than its factorization.

27997644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1950 (or 1948 counting only the distinct ones).

The product of its digits is 762048, while the sum is 48.

The square root of 27997644 is about 5291.2799963714. The cubic root of 27997644 is about 303.6503800396.

The spelling of 27997644 in words is "twenty-seven million, nine hundred ninety-seven thousand, six hundred forty-four".