20601606501 has 120 divisors (see below), whose sum is σ = 37866185280. Its totient is φ = 11098902528.

The previous prime is 20601606499. The next prime is 20601606503. The reversal of 20601606501 is 10560610602.

It is a happy number.

20601606501 is a `hidden beast` number, since 2 + 0 + 6 + 0 + 1 + 6 + 0 + 650 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (20601606499) and next prime (20601606503).

It is not a de Polignac number, because 20601606501 - 2¹ = 20601606499 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20601606503) 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 119 ways as a sum of consecutive naturals, for example, 19380096 + ... + 19381158.

It is an arithmetic number, because the mean of its divisors is an integer number (315551544).

Almost surely, 2^20601606501 is an apocalyptic number.

20601606501 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20601606501 is a deficient number, since it is larger than the sum of its proper divisors (17264578779).

20601606501 is a wasteful number, since it uses less digits than its factorization.

20601606501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1365 (or 1349 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The spelling of 20601606501 in words is "twenty billion, six hundred one million, six hundred six thousand, five hundred one".