385661869 has 4 divisors (see below), whose sum is σ = 386495296. Its totient is φ = 384828444.

The previous prime is 385661839. The next prime is 385661873. The reversal of 385661869 is 968166583.

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: 968166583 = 47 ⋅20599289.

It is a cyclic number.

It is not a de Polignac number, because 385661869 - 2¹¹ = 385659821 is a prime.

It is a super-2 number, since 2×385661869² = 297470154401146322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (385661839) 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, 416019 + ... + 416944.

It is an arithmetic number, because the mean of its divisors is an integer number (96623824).

Almost surely, 2^385661869 is an apocalyptic number.

It is an amenable number.

385661869 is a deficient number, since it is larger than the sum of its proper divisors (833427).

385661869 is an equidigital number, since it uses as much as digits as its factorization.

385661869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 833426.

The product of its digits is 1866240, while the sum is 52.

The square root of 385661869 is about 19638.2756116722. The cubic root of 385661869 is about 727.8952754855.

The spelling of 385661869 in words is "three hundred eighty-five million, six hundred sixty-one thousand, eight hundred sixty-nine".