20728115 has 8 divisors (see below), whose sum is σ = 24917760. Its totient is φ = 16553152.

The previous prime is 20728109. The next prime is 20728121. The reversal of 20728115 is 51182702.

It is an interprime number because it is at equal distance from previous prime (20728109) and next prime (20728121).

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20728115 - 2¹² = 20724019 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 275 + ... + 6444.

It is an arithmetic number, because the mean of its divisors is an integer number (3114720).

Almost surely, 2^20728115 is an apocalyptic number.

20728115 is a deficient number, since it is larger than the sum of its proper divisors (4189645).

20728115 is an equidigital number, since it uses as much as digits as its factorization.

20728115 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7341.

The product of its (nonzero) digits is 1120, while the sum is 26.

The square root of 20728115 is about 4552.8139650111. The cubic root of 20728115 is about 274.6965909901.

The spelling of 20728115 in words is "twenty million, seven hundred twenty-eight thousand, one hundred fifteen".