137828321 has 4 divisors (see below), whose sum is σ = 137970372. Its totient is φ = 137686272.

The previous prime is 137828311. The next prime is 137828323. The reversal of 137828321 is 123828731.

137828321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 89038096 + 48790225 = 9436^2 + 6985^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-137828321 is a prime.

It is a super-3 number, since 3×137828321³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (137828323) 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, 69560 + ... + 71513.

It is an arithmetic number, because the mean of its divisors is an integer number (34492593).

Almost surely, 2^137828321 is an apocalyptic number.

It is an amenable number.

137828321 is a deficient number, since it is larger than the sum of its proper divisors (142051).

137828321 is an equidigital number, since it uses as much as digits as its factorization.

137828321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142050.

The product of its digits is 16128, while the sum is 35.

The square root of 137828321 is about 11740.0307069445. The cubic root of 137828321 is about 516.5505423842.

The spelling of 137828321 in words is "one hundred thirty-seven million, eight hundred twenty-eight thousand, three hundred twenty-one".