20284155 has 32 divisors (see below), whose sum is σ = 36456000. Its totient is φ = 10699776.

The previous prime is 20284151. The next prime is 20284181. The reversal of 20284155 is 55148202.

It is a happy number.

It is not a de Polignac number, because 20284155 - 2² = 20284151 is a prime.

It is a super-2 number, since 2×20284155² = 822893888128050, which contains 22 as substring.

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 (20284151) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12321 + ... + 13869.

It is an arithmetic number, because the mean of its divisors is an integer number (1139250).

Almost surely, 2^20284155 is an apocalyptic number.

20284155 is a deficient number, since it is larger than the sum of its proper divisors (16171845).

20284155 is a wasteful number, since it uses less digits than its factorization.

20284155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1660 (or 1654 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 27.

The square root of 20284155 is about 4503.7934011231. The cubic root of 20284155 is about 272.7212466850.

The spelling of 20284155 in words is "twenty million, two hundred eighty-four thousand, one hundred fifty-five".