28166940 has 60 divisors (see below), whose sum is σ = 88365816. Its totient is φ = 7510752.

The previous prime is 28166939. The next prime is 28166947. The reversal of 28166940 is 4966182.

It is a tau number, because it is divible by the number of its divisors (60).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 28166895 and 28166904.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28166947) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 7074 + ... + 10313.

Almost surely, 2^28166940 is an apocalyptic number.

28166940 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28166940 is an abundant number, since it is smaller than the sum of its proper divisors (60198876).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28166940 is a wasteful number, since it uses less digits than its factorization.

28166940 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17408 (or 17397 counting only the distinct ones).

The product of its (nonzero) digits is 20736, while the sum is 36.

The square root of 28166940 is about 5307.2535270138. The cubic root of 28166940 is about 304.2611876964.

The spelling of 28166940 in words is "twenty-eight million, one hundred sixty-six thousand, nine hundred forty".