20647730 has 16 divisors (see below), whose sum is σ = 37217664. Its totient is φ = 8247600.

The previous prime is 20647727. The next prime is 20647747. The reversal of 20647730 is 3774602.

It is a junction number, because it is equal to n+sod(n) for n = 20647693 and 20647702.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 13505 + ... + 14955.

It is an arithmetic number, because the mean of its divisors is an integer number (2326104).

Almost surely, 2^20647730 is an apocalyptic number.

20647730 is a deficient number, since it is larger than the sum of its proper divisors (16569934).

20647730 is a wasteful number, since it uses less digits than its factorization.

20647730 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2881.

The product of its (nonzero) digits is 7056, while the sum is 29.

The square root of 20647730 is about 4543.9773326899. The cubic root of 20647730 is about 274.3410337898.

The spelling of 20647730 in words is "twenty million, six hundred forty-seven thousand, seven hundred thirty".