155640 has 32 divisors (see below), whose sum is σ = 467280. Its totient is φ = 41472.

The previous prime is 155627. The next prime is 155653. The reversal of 155640 is 46551.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (155627) and next prime (155653).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 529 + ... + 768.

2¹⁵⁵⁶⁴⁰ is an apocalyptic number.

155640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

155640 is an abundant number, since it is smaller than the sum of its proper divisors (311640).

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

155640 is a wasteful number, since it uses less digits than its factorization.

155640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1311 (or 1307 counting only the distinct ones).

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 155640 is about 394.5123572209. The cubic root of 155640 is about 53.7906848989.

It can be divided in two parts, 1556 and 40, that added together give a triangular number (1596 = T₅₆).

The spelling of 155640 in words is "one hundred fifty-five thousand, six hundred forty".