28417997 has 4 divisors (see below), whose sum is σ = 28536156. Its totient is φ = 28299840.

The previous prime is 28417981. The next prime is 28418029. The reversal of 28417997 is 79971482.

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 17255716 + 11162281 = 4154^2 + 3341^2 .

It is a cyclic number.

It is not a de Polignac number, because 28417997 - 2⁴ = 28417981 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28417927) 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, 58718 + ... + 59199.

It is an arithmetic number, because the mean of its divisors is an integer number (7134039).

Almost surely, 2^28417997 is an apocalyptic number.

It is an amenable number.

28417997 is a deficient number, since it is larger than the sum of its proper divisors (118159).

28417997 is a wasteful number, since it uses less digits than its factorization.

28417997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 118158.

The product of its digits is 254016, while the sum is 47.

The square root of 28417997 is about 5330.8533088053. The cubic root of 28417997 is about 305.1624933655.

It can be divided in two parts, 284 and 17997, that added together give a palindrome (18281).

The spelling of 28417997 in words is "twenty-eight million, four hundred seventeen thousand, nine hundred ninety-seven".