20285155 has 16 divisors (see below), whose sum is σ = 26707968. Its totient is φ = 14668000.

The previous prime is 20285099. The next prime is 20285263. The reversal of 20285155 is 55158202.

It is a de Polignac number, because none of the positive numbers 2^k-20285155 is a prime.

It is a super-2 number, since 2×20285155² = 822975026748050, which contains 22 as substring.

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 15 ways as a sum of consecutive naturals, for example, 9540 + ... + 11470.

It is an arithmetic number, because the mean of its divisors is an integer number (1669248).

Almost surely, 2^20285155 is an apocalyptic number.

20285155 is a deficient number, since it is larger than the sum of its proper divisors (6422813).

20285155 is a wasteful number, since it uses less digits than its factorization.

20285155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2138.

The product of its (nonzero) digits is 4000, while the sum is 28.

The square root of 20285155 is about 4503.9044172806. The cubic root of 20285155 is about 272.7257282909.

The spelling of 20285155 in words is "twenty million, two hundred eighty-five thousand, one hundred fifty-five".