388642481 has 4 divisors (see below), whose sum is σ = 395975412. Its totient is φ = 381309552.

The previous prime is 388642469. The next prime is 388642489. The reversal of 388642481 is 184246883.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 184246883 = 3701 ⋅49783.

It can be written as a sum of positive squares in 2 ways, for example, as 228493456 + 160149025 = 15116^2 + 12655^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-388642481 is a prime.

It is a super-2 number, since 2×388642481² = 302085956075670722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (388642489) 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, 3666386 + ... + 3666491.

It is an arithmetic number, because the mean of its divisors is an integer number (98993853).

Almost surely, 2^388642481 is an apocalyptic number.

It is an amenable number.

388642481 is a deficient number, since it is larger than the sum of its proper divisors (7332931).

388642481 is an equidigital number, since it uses as much as digits as its factorization.

388642481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7332930.

The product of its digits is 294912, while the sum is 44.

The square root of 388642481 is about 19714.0173734325. The cubic root of 388642481 is about 729.7656600667.

The spelling of 388642481 in words is "three hundred eighty-eight million, six hundred forty-two thousand, four hundred eighty-one".