27981745 has 16 divisors (see below), whose sum is σ = 38786688. Its totient is φ = 19152640.

The previous prime is 27981727. The next prime is 27981763. The reversal of 27981745 is 54718972.

It is an interprime number because it is at equal distance from previous prime (27981727) and next prime (27981763).

It is not a de Polignac number, because 27981745 - 2⁷ = 27981617 is a prime.

It is a Duffinian number.

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, 14029 + ... + 15898.

It is an arithmetic number, because the mean of its divisors is an integer number (2424168).

Almost surely, 2^27981745 is an apocalyptic number.

It is an amenable number.

27981745 is a deficient number, since it is larger than the sum of its proper divisors (10804943).

27981745 is a wasteful number, since it uses less digits than its factorization.

27981745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29960.

The product of its digits is 141120, while the sum is 43.

The square root of 27981745 is about 5289.7774055247. Note that the first 3 decimals coincide. The cubic root of 27981745 is about 303.5928912556.

The spelling of 27981745 in words is "twenty-seven million, nine hundred eighty-one thousand, seven hundred forty-five".