28197760 has 32 divisors (see below), whose sum is σ = 67411800. Its totient is φ = 11278848.

The previous prime is 28197739. The next prime is 28197779. The reversal of 28197760 is 6779182.

It is a tau number, because it is divible by the number of its divisors (32).

It is a super-2 number, since 2×28197760² = 1590227338035200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (40).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 21390 + ... + 22669.

Almost surely, 2^28197760 is an apocalyptic number.

28197760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28197760 is an abundant number, since it is smaller than the sum of its proper divisors (39214040).

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

28197760 is an equidigital number, since it uses as much as digits as its factorization.

28197760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44078 (or 44066 counting only the distinct ones).

The product of its (nonzero) digits is 42336, while the sum is 40.

The square root of 28197760 is about 5310.1563065507. The cubic root of 28197760 is about 304.3721204860.

The spelling of 28197760 in words is "twenty-eight million, one hundred ninety-seven thousand, seven hundred sixty".