20661620526 has 24 divisors (see below), whose sum is σ = 44773312584. Its totient is φ = 6886211760.

The previous prime is 20661620503. The next prime is 20661620527. The reversal of 20661620526 is 62502616602.

20661620526 is a `hidden beast` number, since 2 + 0 + 6 + 6 + 1 + 620 + 5 + 26 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20661620527) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 50961 + ... + 209571.

It is an arithmetic number, because the mean of its divisors is an integer number (1865554691).

Almost surely, 2^20661620526 is an apocalyptic number.

20661620526 is an abundant number, since it is smaller than the sum of its proper divisors (24111692058).

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

20661620526 is a wasteful number, since it uses less digits than its factorization.

20661620526 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165856 (or 165853 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 36.

The spelling of 20661620526 in words is "twenty billion, six hundred sixty-one million, six hundred twenty thousand, five hundred twenty-six".