20506515028 has 6 divisors (see below), whose sum is σ = 35886401306. Its totient is φ = 10253257512.

The previous prime is 20506514993. The next prime is 20506515049. The reversal of 20506515028 is 82051560502.

It can be written as a sum of positive squares in only one way, i.e., 15699588804 + 4806926224 = 125298^2 + 69332^2 .

It is a junction number, because it is equal to n+sod(n) for n = 20506514984 and 20506515002.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2563314375 + ... + 2563314382.

Almost surely, 2^20506515028 is an apocalyptic number.

It is an amenable number.

20506515028 is a deficient number, since it is larger than the sum of its proper divisors (15379886278).

20506515028 is a wasteful number, since it uses less digits than its factorization.

20506515028 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5126628761 (or 5126628759 counting only the distinct ones).

The product of its (nonzero) digits is 24000, while the sum is 34.

The spelling of 20506515028 in words is "twenty billion, five hundred six million, five hundred fifteen thousand, twenty-eight".