385778281 has 4 divisors (see below), whose sum is σ = 440889472. Its totient is φ = 330667092.

The previous prime is 385778269. The next prime is 385778311. The reversal of 385778281 is 182877583.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 182877583 = 7 ⋅26125369.

It is not a de Polignac number, because 385778281 - 2⁵ = 385778249 is a prime.

It is a super-2 number, since 2×385778281² = 297649764182629922, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (385778201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27555585 + ... + 27555598.

It is an arithmetic number, because the mean of its divisors is an integer number (110222368).

Almost surely, 2^385778281 is an apocalyptic number.

It is an amenable number.

385778281 is a deficient number, since it is larger than the sum of its proper divisors (55111191).

385778281 is an equidigital number, since it uses as much as digits as its factorization.

385778281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55111190.

The product of its digits is 752640, while the sum is 49.

The square root of 385778281 is about 19641.2392938939. The cubic root of 385778281 is about 727.9685064919.

The spelling of 385778281 in words is "three hundred eighty-five million, seven hundred seventy-eight thousand, two hundred eighty-one".