20566407501 has 6 divisors (see below), whose sum is σ = 29707033070. Its totient is φ = 13710938328.

The previous prime is 20566407479. The next prime is 20566407503. The reversal of 20566407501 is 10570466502.

It is a happy number.

20566407501 is a `hidden beast` number, since 2 + 0 + 5 + 6 + 640 + 7 + 5 + 0 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 12690022500 + 7876385001 = 112650^2 + 88749^2 .

It is not a de Polignac number, because 20566407501 - 2⁹ = 20566406989 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20566407503) 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 5 ways as a sum of consecutive naturals, for example, 1142578186 + ... + 1142578203.

Almost surely, 2^20566407501 is an apocalyptic number.

It is an amenable number.

20566407501 is a deficient number, since it is larger than the sum of its proper divisors (9140625569).

20566407501 is a wasteful number, since it uses less digits than its factorization.

20566407501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2285156395 (or 2285156392 counting only the distinct ones).

The product of its (nonzero) digits is 50400, while the sum is 36.

The spelling of 20566407501 in words is "twenty billion, five hundred sixty-six million, four hundred seven thousand, five hundred one".