20530521145 has 16 divisors (see below), whose sum is σ = 25720002000. Its totient is φ = 15712558848.

The previous prime is 20530521131. The next prime is 20530521173. The reversal of 20530521145 is 54112503502.

It can be written as a sum of positive squares in 8 ways, for example, as 392356864 + 20138164281 = 19808^2 + 141909^2 .

It is a cyclic number.

It is not a de Polignac number, because 20530521145 - 2¹³ = 20530512953 is a prime.

It is a super-2 number, since 2×20530521145² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

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 15 ways as a sum of consecutive naturals, for example, 633690 + ... + 665299.

It is an arithmetic number, because the mean of its divisors is an integer number (1607500125).

Almost surely, 2^20530521145 is an apocalyptic number.

It is an amenable number.

20530521145 is a deficient number, since it is larger than the sum of its proper divisors (5189480855).

20530521145 is a wasteful number, since it uses less digits than its factorization.

20530521145 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1299132.

The product of its (nonzero) digits is 6000, while the sum is 28.

The spelling of 20530521145 in words is "twenty billion, five hundred thirty million, five hundred twenty-one thousand, one hundred forty-five".