20647470 has 16 divisors (see below), whose sum is σ = 49554000. Its totient is φ = 5505984.

The previous prime is 20647453. The next prime is 20647489. The reversal of 20647470 is 7474602.

It is a Harshad number since it is a multiple of its sum of digits (30), and also a Moran number because the ratio is a prime number: 688249 = 20647470 / (2 + 0 + 6 + 4 + 7 + 4 + 7 + 0).

It is a Curzon number.

It is a congruent number.

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, 344095 + ... + 344154.

It is an arithmetic number, because the mean of its divisors is an integer number (3097125).

Almost surely, 2^20647470 is an apocalyptic number.

20647470 is an abundant number, since it is smaller than the sum of its proper divisors (28906530).

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

20647470 is a wasteful number, since it uses less digits than its factorization.

20647470 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 688259.

The product of its (nonzero) digits is 9408, while the sum is 30.

The square root of 20647470 is about 4543.9487233022. The cubic root of 20647470 is about 274.3398822674.

The spelling of 20647470 in words is "twenty million, six hundred forty-seven thousand, four hundred seventy".