20661620530 has 8 divisors (see below), whose sum is σ = 37190916972. Its totient is φ = 8264648208.

The previous prime is 20661620527. The next prime is 20661620537. The reversal of 20661620530 is 3502616602.

It can be written as a sum of positive squares in 2 ways, for example, as 20479613449 + 182007081 = 143107^2 + 13491^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 20661620492 and 20661620501.

It is not an unprimeable number, because it can be changed into a prime (20661620537) 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 3 ways as a sum of consecutive naturals, for example, 1033081017 + ... + 1033081036.

Almost surely, 2^20661620530 is an apocalyptic number.

20661620530 is a deficient number, since it is larger than the sum of its proper divisors (16529296442).

20661620530 is a wasteful number, since it uses less digits than its factorization.

20661620530 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2066162060.

The product of its (nonzero) digits is 12960, while the sum is 31.

The spelling of 20661620530 in words is "twenty billion, six hundred sixty-one million, six hundred twenty thousand, five hundred thirty".