27645540 has 144 divisors (see below), whose sum is σ = 88444608. Its totient is φ = 6412032.

The previous prime is 27645511. The next prime is 27645547. The reversal of 27645540 is 4554672.

27645540 = T₃₂₅ + T₃₂₆ + ... + T₅₈₄.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27645547) 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 in 47 ways as a sum of consecutive naturals, for example, 412587 + ... + 412653.

Almost surely, 2^27645540 is an apocalyptic number.

27645540 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 27645540, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (44222304).

27645540 is an abundant number, since it is smaller than the sum of its proper divisors (60799068).

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

27645540 is a wasteful number, since it uses less digits than its factorization.

27645540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138 (or 113 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 33.

The square root of 27645540 is about 5257.9026236704. The cubic root of 27645540 is about 302.3720835207.

The spelling of 27645540 in words is "twenty-seven million, six hundred forty-five thousand, five hundred forty".