20102156 has 24 divisors (see below), whose sum is σ = 36512784. Its totient is φ = 9676800.

The previous prime is 20102153. The next prime is 20102213. The reversal of 20102156 is 65120102.

It is not an unprimeable number, because it can be changed into a prime (20102153) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11756 + ... + 13356.

It is an arithmetic number, because the mean of its divisors is an integer number (1521366).

Almost surely, 2^20102156 is an apocalyptic number.

It is an amenable number.

20102156 is a deficient number, since it is larger than the sum of its proper divisors (16410628).

20102156 is a wasteful number, since it uses less digits than its factorization.

20102156 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1721 (or 1719 counting only the distinct ones).

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 20102156 is about 4483.5427956026. The cubic root of 20102156 is about 271.9031337601.

Adding to 20102156 its reverse (65120102), we get a palindrome (85222258).

The spelling of 20102156 in words is "twenty million, one hundred two thousand, one hundred fifty-six".