137398321 has 4 divisors (see below), whose sum is σ = 137483892. Its totient is φ = 137312752.

The previous prime is 137398319. The next prime is 137398351. The reversal of 137398321 is 123893731.

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 51279921 + 86118400 = 7161^2 + 9280^2 .

It is a cyclic number.

It is not a de Polignac number, because 137398321 - 2¹ = 137398319 is a prime.

It is a super-2 number, since 2×137398321² = 37756597227238082, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (137398351) 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, 40330 + ... + 43603.

It is an arithmetic number, because the mean of its divisors is an integer number (34370973).

Almost surely, 2^137398321 is an apocalyptic number.

It is an amenable number.

137398321 is a deficient number, since it is larger than the sum of its proper divisors (85571).

137398321 is an equidigital number, since it uses as much as digits as its factorization.

137398321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85570.

The product of its digits is 27216, while the sum is 37.

The square root of 137398321 is about 11721.7029906068. The cubic root of 137398321 is about 516.0128006459.

The spelling of 137398321 in words is "one hundred thirty-seven million, three hundred ninety-eight thousand, three hundred twenty-one".