155105231 has 4 divisors (see below), whose sum is σ = 156704352. Its totient is φ = 153506112.

The previous prime is 155105213. The next prime is 155105239. The reversal of 155105231 is 132501551.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-155105231 is a prime.

It is a super-2 number, since 2×155105231² = 48115265367126722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 155105197 and 155105206.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (155105239) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 799415 + ... + 799608.

It is an arithmetic number, because the mean of its divisors is an integer number (39176088).

Almost surely, 2^155105231 is an apocalyptic number.

155105231 is a deficient number, since it is larger than the sum of its proper divisors (1599121).

155105231 is an equidigital number, since it uses as much as digits as its factorization.

155105231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1599120.

The product of its (nonzero) digits is 750, while the sum is 23.

The square root of 155105231 is about 12454.1250595937. The cubic root of 155105231 is about 537.2900709671.

Adding to 155105231 its reverse (132501551), we get a palindrome (287606782).

The spelling of 155105231 in words is "one hundred fifty-five million, one hundred five thousand, two hundred thirty-one".