285211381 has 16 divisors (see below), whose sum is σ = 353282944. Its totient is φ = 224213184.

The previous prime is 285211373. The next prime is 285211387. The reversal of 285211381 is 183112582.

It is not a de Polignac number, because 285211381 - 2³ = 285211373 is a prime.

It is a super-2 number, since 2×285211381² = 162691063703854322, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (285211387) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4306 + ... + 24268.

It is an arithmetic number, because the mean of its divisors is an integer number (22080184).

Almost surely, 2^285211381 is an apocalyptic number.

It is an amenable number.

285211381 is a deficient number, since it is larger than the sum of its proper divisors (68071563).

285211381 is a wasteful number, since it uses less digits than its factorization.

285211381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20140.

The product of its digits is 3840, while the sum is 31.

The square root of 285211381 is about 16888.2024206249. The cubic root of 285211381 is about 658.2470940320.

The spelling of 285211381 in words is "two hundred eighty-five million, two hundred eleven thousand, three hundred eighty-one".