20647470420 has 72 divisors (see below), whose sum is σ = 62992782216. Its totient is φ = 5474157312.

The previous prime is 20647470419. The next prime is 20647470421. The reversal of 20647470420 is 2407474602.

It is a happy number.

20647470420 is a `hidden beast` number, since 2 + 0 + 647 + 4 + 7 + 0 + 4 + 2 + 0 = 666.

It is an interprime number because it is at equal distance from previous prime (20647470419) and next prime (20647470421).

It can be written as a sum of positive squares in 4 ways, for example, as 8002018116 + 12645452304 = 89454^2 + 112452^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20647470421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 300387 + ... + 362666.

It is an arithmetic number, because the mean of its divisors is an integer number (874899753).

Almost surely, 2^20647470420 is an apocalyptic number.

20647470420 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20647470420 is an abundant number, since it is smaller than the sum of its proper divisors (42345311796).

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

20647470420 is a wasteful number, since it uses less digits than its factorization.

20647470420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 663241 (or 663236 counting only the distinct ones).

The product of its (nonzero) digits is 75264, while the sum is 36.

The spelling of 20647470420 in words is "twenty billion, six hundred forty-seven million, four hundred seventy thousand, four hundred twenty".