20156101 has 12 divisors (see below), whose sum is σ = 24827148. Its totient is φ = 16259712.

The previous prime is 20156099. The next prime is 20156117. The reversal of 20156101 is 10165102.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 10233601 + 9922500 = 3199^2 + 3150^2 .

It is not a de Polignac number, because 20156101 - 2¹ = 20156099 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 (20156401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11266 + ... + 12931.

It is an arithmetic number, because the mean of its divisors is an integer number (2068929).

Almost surely, 2^20156101 is an apocalyptic number.

It is an amenable number.

20156101 is a deficient number, since it is larger than the sum of its proper divisors (4671047).

20156101 is a wasteful number, since it uses less digits than its factorization.

20156101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24228 (or 24221 counting only the distinct ones).

The product of its (nonzero) digits is 60, while the sum is 16.

The square root of 20156101 is about 4489.5546549741. The cubic root of 20156101 is about 272.1461377693.

Subtracting from 20156101 its reverse (10165102), we obtain a palindrome (9990999).

The spelling of 20156101 in words is "twenty million, one hundred fifty-six thousand, one hundred one".