28697760 has 384 divisors, whose sum is σ = 125314560. Its totient is φ = 5971968.

The previous prime is 28697743. The next prime is 28697761. The reversal of 28697760 is 6779682.

It is a happy number.

It is a super-2 number, since 2×28697760² = 1647122858035200, which contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a Saint-Exupery number, since it is equal to the product of the sides of a Pythagorean triangle: 730 × 54 × 728.

It is not an unprimeable number, because it can be changed into a prime (28697761) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 393084 + ... + 393156.

It is an arithmetic number, because the mean of its divisors is an integer number (326340).

Almost surely, 2^28697760 is an apocalyptic number.

28697760 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 28697760, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (62657280).

28697760 is an abundant number, since it is smaller than the sum of its proper divisors (96616800).

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

28697760 is a wasteful number, since it uses less digits than its factorization.

28697760 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 117 (or 103 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 45.

The square root of 28697760 is about 5357.0290273621. The cubic root of 28697760 is about 306.1606230925.

The spelling of 28697760 in words is "twenty-eight million, six hundred ninety-seven thousand, seven hundred sixty".