385021581 has 16 divisors (see below), whose sum is σ = 605626368. Its totient is φ = 212914800.

The previous prime is 385021579. The next prime is 385021601. The reversal of 385021581 is 185120583.

It is a happy number.

It is not a de Polignac number, because 385021581 - 2¹ = 385021579 is a prime.

It is a super-2 number, since 2×385021581² = 296483235671479122, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (385021531) 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, 295065 + ... + 296366.

It is an arithmetic number, because the mean of its divisors is an integer number (37851648).

Almost surely, 2^385021581 is an apocalyptic number.

385021581 is a gapful number since it is divisible by the number (31) formed by its first and last digit.

It is an amenable number.

385021581 is a deficient number, since it is larger than the sum of its proper divisors (220604787).

385021581 is a wasteful number, since it uses less digits than its factorization.

385021581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 591472.

The product of its (nonzero) digits is 9600, while the sum is 33.

The square root of 385021581 is about 19621.9667974441. The cubic root of 385021581 is about 727.4922274532.

The spelling of 385021581 in words is "three hundred eighty-five million, twenty-one thousand, five hundred eighty-one".