38728961 has 4 divisors (see below), whose sum is σ = 39363924. Its totient is φ = 38094000.

The previous prime is 38728931. The next prime is 38728979. The reversal of 38728961 is 16982783.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3682561 + 35046400 = 1919^2 + 5920^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-38728961 is a prime.

It is a super-4 number, since 4×38728961⁴ (a number of 31 digits) contains 4444 as substring.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (38728931) 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, 317390 + ... + 317511.

It is an arithmetic number, because the mean of its divisors is an integer number (9840981).

Almost surely, 2^38728961 is an apocalyptic number.

It is an amenable number.

38728961 is a deficient number, since it is larger than the sum of its proper divisors (634963).

38728961 is an equidigital number, since it uses as much as digits as its factorization.

38728961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 634962.

The product of its digits is 145152, while the sum is 44.

The square root of 38728961 is about 6223.2596764075. The cubic root of 38728961 is about 338.3337185778. Note that the first 3 decimals are identical.

The spelling of 38728961 in words is "thirty-eight million, seven hundred twenty-eight thousand, nine hundred sixty-one".