27642780 has 144 divisors (see below), whose sum is σ = 95606784. Its totient is φ = 6399360.

The previous prime is 27642779. The next prime is 27642787. The reversal of 27642780 is 8724672.

27642780 is a `hidden beast` number, since 2 + 7 + 642 + 7 + 8 + 0 = 666.

It is a super-2 number, since 2×27642780² = 1528246572256800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27642787) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 45237 + ... + 45843.

It is an arithmetic number, because the mean of its divisors is an integer number (663936).

Almost surely, 2^27642780 is an apocalyptic number.

27642780 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 27642780, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47803392).

27642780 is an abundant number, since it is smaller than the sum of its proper divisors (67964004).

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

27642780 is a wasteful number, since it uses less digits than its factorization.

27642780 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 656 (or 651 counting only the distinct ones).

The product of its (nonzero) digits is 37632, while the sum is 36.

The square root of 27642780 is about 5257.6401550506. The cubic root of 27642780 is about 302.3620207195.

The spelling of 27642780 in words is "twenty-seven million, six hundred forty-two thousand, seven hundred eighty".