137840 has 20 divisors (see below), whose sum is σ = 320664. Its totient is φ = 55104.

The previous prime is 137831. The next prime is 137849. The reversal of 137840 is 48731.

137840 = T₁₂₈ + T₁₂₉ + ... + T₁₄₂.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (137831) and next prime (137849).

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (137849) by changing a digit.

137840 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 782 + ... + 941.

2¹³⁷⁸⁴⁰ is an apocalyptic number.

137840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

137840 is an abundant number, since it is smaller than the sum of its proper divisors (182824).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

137840 is a wasteful number, since it uses less digits than its factorization.

137840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1736 (or 1730 counting only the distinct ones).

The product of its (nonzero) digits is 672, while the sum is 23.

The square root of 137840 is about 371.2680972020. The cubic root of 137840 is about 51.6565132089.

The spelling of 137840 in words is "one hundred thirty-seven thousand, eight hundred forty".