27550981 has 4 divisors (see below), whose sum is σ = 27674752. Its totient is φ = 27427212.

The previous prime is 27550979. The next prime is 27550997. The reversal of 27550981 is 18905572.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 27550981 - 2¹ = 27550979 is a prime.

It is a super-2 number, since 2×27550981² = 1518113108124722, which contains 22 as substring.

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 27550981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27550951) 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, 61551 + ... + 61996.

It is an arithmetic number, because the mean of its divisors is an integer number (6918688).

Almost surely, 2^27550981 is an apocalyptic number.

It is an amenable number.

27550981 is a deficient number, since it is larger than the sum of its proper divisors (123771).

27550981 is a wasteful number, since it uses less digits than its factorization.

27550981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 123770.

The product of its (nonzero) digits is 25200, while the sum is 37.

The square root of 27550981 is about 5248.9028377367. The cubic root of 27550981 is about 302.0269445135.

The spelling of 27550981 in words is "twenty-seven million, five hundred fifty thousand, nine hundred eighty-one".