20042155 has 8 divisors (see below), whose sum is σ = 27486432. Its totient is φ = 13743168.

The previous prime is 20042117. The next prime is 20042173. The reversal of 20042155 is 55124002.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20042155 is a prime.

It is a Duffinian number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 286282 + ... + 286351.

It is an arithmetic number, because the mean of its divisors is an integer number (3435804).

Almost surely, 2^20042155 is an apocalyptic number.

20042155 is a deficient number, since it is larger than the sum of its proper divisors (7444277).

20042155 is an equidigital number, since it uses as much as digits as its factorization.

20042155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 572645.

The product of its (nonzero) digits is 400, while the sum is 19.

The square root of 20042155 is about 4476.8465463985. The cubic root of 20042155 is about 271.6323382839.

Adding to 20042155 its reverse (55124002), we get a palindrome (75166157).

The spelling of 20042155 in words is "twenty million, forty-two thousand, one hundred fifty-five".