28163961 has 24 divisors (see below), whose sum is σ = 47024640. Its totient is φ = 15909696.

The previous prime is 28163953. The next prime is 28163963. The reversal of 28163961 is 16936182.

It is not a de Polignac number, because 28163961 - 2³ = 28163953 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28163963) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3096 + ... + 8118.

It is an arithmetic number, because the mean of its divisors is an integer number (1959360).

Almost surely, 2^28163961 is an apocalyptic number.

28163961 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

28163961 is a deficient number, since it is larger than the sum of its proper divisors (18860679).

28163961 is a wasteful number, since it uses less digits than its factorization.

28163961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5125 (or 5122 counting only the distinct ones).

The product of its digits is 15552, while the sum is 36.

The square root of 28163961 is about 5306.9728659566. The cubic root of 28163961 is about 304.2504608651.

The spelling of 28163961 in words is "twenty-eight million, one hundred sixty-three thousand, nine hundred sixty-one".