155815 has 8 divisors (see below), whose sum is σ = 204048. Its totient is φ = 113280.

The previous prime is 155809. The next prime is 155821. The reversal of 155815 is 518551.

It is an interprime number because it is at equal distance from previous prime (155809) and next prime (155821).

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

It is not a de Polignac number, because 155815 - 2⁵ = 155783 is a prime.

It is a Duffinian number.

155815 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 155815.

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, 1362 + ... + 1471.

It is an arithmetic number, because the mean of its divisors is an integer number (25506).

2¹⁵⁵⁸¹⁵ is an apocalyptic number.

155815 is a deficient number, since it is larger than the sum of its proper divisors (48233).

155815 is a wasteful number, since it uses less digits than its factorization.

155815 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2849.

The product of its digits is 1000, while the sum is 25.

The square root of 155815 is about 394.7340877097. The cubic root of 155815 is about 53.8108379100.

The spelling of 155815 in words is "one hundred fifty-five thousand, eight hundred fifteen".