27706640 has 40 divisors (see below), whose sum is σ = 69375768. Its totient is φ = 10229760.

The previous prime is 27706597. The next prime is 27706649. The reversal of 27706640 is 4660772.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 541696 + 27164944 = 736^2 + 5212^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a junction number, because it is equal to n+sod(n) for n = 27706597 and 27706606.

It is not an unprimeable number, because it can be changed into a prime (27706649) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12281 + ... + 14360.

Almost surely, 2^27706640 is an apocalyptic number.

27706640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

27706640 is an abundant number, since it is smaller than the sum of its proper divisors (41669128).

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

27706640 is a wasteful number, since it uses less digits than its factorization.

27706640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26667 (or 26661 counting only the distinct ones).

The product of its (nonzero) digits is 14112, while the sum is 32.

The square root of 27706640 is about 5263.7097184400. The cubic root of 27706640 is about 302.5946792857.

The spelling of 27706640 in words is "twenty-seven million, seven hundred six thousand, six hundred forty".