20728574 has 4 divisors (see below), whose sum is σ = 31092864. Its totient is φ = 10364286.

The previous prime is 20728571. The next prime is 20728577. The reversal of 20728574 is 47582702.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 47582702 = 2 ⋅23791351.

It is an interprime number because it is at equal distance from previous prime (20728571) and next prime (20728577).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20728571) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5182142 + ... + 5182145.

It is an arithmetic number, because the mean of its divisors is an integer number (7773216).

Almost surely, 2^20728574 is an apocalyptic number.

20728574 is a deficient number, since it is larger than the sum of its proper divisors (10364290).

20728574 is a wasteful number, since it uses less digits than its factorization.

20728574 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10364289.

The product of its (nonzero) digits is 31360, while the sum is 35.

The square root of 20728574 is about 4552.8643731172. The cubic root of 20728574 is about 274.6986185873.

The spelling of 20728574 in words is "twenty million, seven hundred twenty-eight thousand, five hundred seventy-four".