27643440 has 160 divisors (see below), whose sum is σ = 96350976. Its totient is φ = 6497280.

The previous prime is 27643433. The next prime is 27643459. The reversal of 27643440 is 4434672.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 27643398 and 27643407.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 97539 + ... + 97821.

Almost surely, 2^27643440 is an apocalyptic number.

27643440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 27643440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48175488).

27643440 is an abundant number, since it is smaller than the sum of its proper divisors (68707536).

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

27643440 is a wasteful number, since it uses less digits than its factorization.

27643440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 347 (or 341 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 30.

The square root of 27643440 is about 5257.7029204777. The cubic root of 27643440 is about 302.3644271025.

The spelling of 27643440 in words is "twenty-seven million, six hundred forty-three thousand, four hundred forty".