28669720 has 16 divisors (see below), whose sum is σ = 64506960. Its totient is φ = 11467872.

The previous prime is 28669717. The next prime is 28669721. The reversal of 28669720 is 2796682.

It is a Harshad number since it is a multiple of its sum of digits (40), and also a Moran number because the ratio is a prime number: 716743 = 28669720 / (2 + 8 + 6 + 6 + 9 + 7 + 2 + 0).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28669721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 358332 + ... + 358411.

It is an arithmetic number, because the mean of its divisors is an integer number (4031685).

Almost surely, 2^28669720 is an apocalyptic number.

28669720 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

28669720 is an abundant number, since it is smaller than the sum of its proper divisors (35837240).

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

28669720 is a wasteful number, since it uses less digits than its factorization.

28669720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 716754 (or 716750 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 40.

The square root of 28669720 is about 5354.4112654894. The cubic root of 28669720 is about 306.0608761507.

The spelling of 28669720 in words is "twenty-eight million, six hundred sixty-nine thousand, seven hundred twenty".