28940505 has 32 divisors (see below), whose sum is σ = 51701760. Its totient is φ = 13702080.

The previous prime is 28940479. The next prime is 28940507. The reversal of 28940505 is 50504982.

It is not a de Polignac number, because 28940505 - 2⁶ = 28940441 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (28940507) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5056 + ... + 9134.

It is an arithmetic number, because the mean of its divisors is an integer number (1615680).

Almost surely, 2^28940505 is an apocalyptic number.

It is an amenable number.

28940505 is a deficient number, since it is larger than the sum of its proper divisors (22761255).

28940505 is a wasteful number, since it uses less digits than its factorization.

28940505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4141.

The product of its (nonzero) digits is 14400, while the sum is 33.

The square root of 28940505 is about 5379.6379989735. The cubic root of 28940505 is about 307.0214381645.

The spelling of 28940505 in words is "twenty-eight million, nine hundred forty thousand, five hundred five".