213728137 has 8 divisors (see below), whose sum is σ = 244944000. Its totient is φ = 182683104.

The previous prime is 213728111. The next prime is 213728161. The reversal of 213728137 is 731827312.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-213728137 is a prime.

It is not an unprimeable number, because it can be changed into a prime (213728737) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 40012 + ... + 45037.

It is an arithmetic number, because the mean of its divisors is an integer number (30618000).

Almost surely, 2^213728137 is an apocalyptic number.

It is an amenable number.

213728137 is a deficient number, since it is larger than the sum of its proper divisors (31215863).

213728137 is an equidigital number, since it uses as much as digits as its factorization.

213728137 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85415.

The product of its digits is 14112, while the sum is 34.

The square root of 213728137 is about 14619.4437992695. The cubic root of 213728137 is about 597.8890046899.

The spelling of 213728137 in words is "two hundred thirteen million, seven hundred twenty-eight thousand, one hundred thirty-seven".