20647128 has 16 divisors (see below), whose sum is σ = 51617880. Its totient is φ = 6882368.

The previous prime is 20647117. The next prime is 20647139. The reversal of 20647128 is 82174602.

It is an interprime number because it is at equal distance from previous prime (20647117) and next prime (20647139).

It is a junction number, because it is equal to n+sod(n) for n = 20647095 and 20647104.

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, 430125 + ... + 430172.

Almost surely, 2^20647128 is an apocalyptic number.

It is an amenable number.

20647128 is an abundant number, since it is smaller than the sum of its proper divisors (30970752).

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

20647128 is a wasteful number, since it uses less digits than its factorization.

20647128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 860306 (or 860302 counting only the distinct ones).

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 20647128 is about 4543.9110906795. The cubic root of 20647128 is about 274.3383675579.

The spelling of 20647128 in words is "twenty million, six hundred forty-seven thousand, one hundred twenty-eight".