Search a number
-
+
28463781 = 316975591
BaseRepresentation
bin110110010010…
…1001010100101
31222120002222010
41230211022211
524241320111
62454024433
7463636533
oct154451245
958502863
1028463781
1115081295
129648119
135b87998
143acd153
152773aa6
hex1b252a5

28463781 has 8 divisors (see below), whose sum is σ = 37980864. Its totient is φ = 18961280.

The previous prime is 28463753. The next prime is 28463801. The reversal of 28463781 is 18736482.

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

It is a cyclic number.

It is not a de Polignac number, because 28463781 - 25 = 28463749 is a prime.

It is a super-2 number, since 2×284637812 = 1620373657631922, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28463711) 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, 2296 + ... + 7886.

It is an arithmetic number, because the mean of its divisors is an integer number (4747608).

Almost surely, 228463781 is an apocalyptic number.

It is an amenable number.

28463781 is a deficient number, since it is larger than the sum of its proper divisors (9517083).

28463781 is a wasteful number, since it uses less digits than its factorization.

28463781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7291.

The product of its digits is 64512, while the sum is 39.

The square root of 28463781 is about 5335.1458274353. The cubic root of 28463781 is about 305.3262870247.

The spelling of 28463781 in words is "twenty-eight million, four hundred sixty-three thousand, seven hundred eighty-one".

Divisors: 1 3 1697 5091 5591 16773 9487927 28463781