27361981 has 4 divisors (see below), whose sum is σ = 28101532. Its totient is φ = 26622432.

The previous prime is 27361969. The next prime is 27361987. The reversal of 27361981 is 18916372.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17089956 + 10272025 = 4134^2 + 3205^2 .

It is a cyclic number.

It is not a de Polignac number, because 27361981 - 2¹¹ = 27359933 is a prime.

It is a super-2 number, since 2×27361981² = 1497356008488722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (37), and also a Moran number because the ratio is a prime number: 739513 = 27361981 / (2 + 7 + 3 + 6 + 1 + 9 + 8 + 1).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 27361981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27361987) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 369720 + ... + 369793.

It is an arithmetic number, because the mean of its divisors is an integer number (7025383).

Almost surely, 2^27361981 is an apocalyptic number.

It is an amenable number.

27361981 is a deficient number, since it is larger than the sum of its proper divisors (739551).

27361981 is an equidigital number, since it uses as much as digits as its factorization.

27361981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 739550.

The product of its digits is 18144, while the sum is 37.

The square root of 27361981 is about 5230.8680923915. The cubic root of 27361981 is about 301.3347232763.

The spelling of 27361981 in words is "twenty-seven million, three hundred sixty-one thousand, nine hundred eighty-one".