137681 has 4 divisors (see below), whose sum is σ = 138864. Its totient is φ = 136500.

The previous prime is 137659. The next prime is 137699. The reversal of 137681 is 186731.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 137681 - 2¹⁰ = 136657 is a prime.

It is a super-2 number, since 2×137681² = 37912115522, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 7.

It is a zygodrome in base 7.

It is a self number, because there is not a number n which added to its sum of digits gives 137681.

It is not an unprimeable number, because it can be changed into a prime (130681) 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, 395 + ... + 656.

It is an arithmetic number, because the mean of its divisors is an integer number (34716).

2¹³⁷⁶⁸¹ is an apocalyptic number.

It is an amenable number.

137681 is a deficient number, since it is larger than the sum of its proper divisors (1183).

137681 is a wasteful number, since it uses less digits than its factorization.

137681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1182.

The product of its digits is 1008, while the sum is 26.

The square root of 137681 is about 371.0539044398. The cubic root of 137681 is about 51.6366434427.

It can be divided in two parts, 137 and 681, that added together give a palindrome (818).

The spelling of 137681 in words is "one hundred thirty-seven thousand, six hundred eighty-one".