137216321 has 16 divisors (see below), whose sum is σ = 156625920. Its totient is φ = 118992720.

The previous prime is 137216293. The next prime is 137216327. The reversal of 137216321 is 123612731.

It is not a de Polignac number, because 137216321 - 2¹⁸ = 136954177 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (137216327) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 166316 + ... + 167138.

It is an arithmetic number, because the mean of its divisors is an integer number (9789120).

Almost surely, 2^137216321 is an apocalyptic number.

137216321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

137216321 is a deficient number, since it is larger than the sum of its proper divisors (19409599).

137216321 is a wasteful number, since it uses less digits than its factorization.

137216321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1516.

The product of its digits is 1512, while the sum is 26.

The square root of 137216321 is about 11713.9370409782. The cubic root of 137216321 is about 515.7848603859.

The spelling of 137216321 in words is "one hundred thirty-seven million, two hundred sixteen thousand, three hundred twenty-one".