28181697 has 8 divisors (see below), whose sum is σ = 38787840. Its totient is φ = 18181680.

The previous prime is 28181689. The next prime is 28181729. The reversal of 28181697 is 79618182.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28181697 - 2³ = 28181689 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28181677) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 151422 + ... + 151607.

It is an arithmetic number, because the mean of its divisors is an integer number (4848480).

Almost surely, 2^28181697 is an apocalyptic number.

It is an amenable number.

28181697 is a deficient number, since it is larger than the sum of its proper divisors (10606143).

28181697 is a wasteful number, since it uses less digits than its factorization.

28181697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 303063.

The product of its digits is 48384, while the sum is 42.

The square root of 28181697 is about 5308.6436120727. The cubic root of 28181697 is about 304.3143137898.

The spelling of 28181697 in words is "twenty-eight million, one hundred eighty-one thousand, six hundred ninety-seven".