27406640 has 80 divisors (see below), whose sum is σ = 67174272. Its totient is φ = 10386432.

The previous prime is 27406637. The next prime is 27406667. The reversal of 27406640 is 4660472.

It is a tau number, because it is divible by the number of its divisors (80).

It is a super-2 number, since 2×27406640² = 1502247832179200, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 139022 + ... + 139218.

Almost surely, 2^27406640 is an apocalyptic number.

27406640 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 27406640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33587136).

27406640 is an abundant number, since it is smaller than the sum of its proper divisors (39767632).

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

27406640 is a wasteful number, since it uses less digits than its factorization.

27406640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 294 (or 288 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 29.

The square root of 27406640 is about 5235.1351462976. The cubic root of 27406640 is about 301.4985758444.

The spelling of 27406640 in words is "twenty-seven million, four hundred six thousand, six hundred forty".