155530031 has 2 divisors, whose sum is σ = 155530032. Its totient is φ = 155530030.

The previous prime is 155529977. The next prime is 155530033. The reversal of 155530031 is 130035551.

155530031 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is an emirp because it is prime and its reverse (130035551) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 155530031 - 2¹⁰ = 155529007 is a prime.

It is a super-2 number, since 2×155530031² = 48379181085721922, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 155530033, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 155529979 and 155530006.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (155530033) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77765015 + 77765016.

It is an arithmetic number, because the mean of its divisors is an integer number (77765016).

Almost surely, 2^155530031 is an apocalyptic number.

155530031 is a deficient number, since it is larger than the sum of its proper divisors (1).

155530031 is an equidigital number, since it uses as much as digits as its factorization.

155530031 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1125, while the sum is 23.

The square root of 155530031 is about 12471.1679886048. The cubic root of 155530031 is about 537.7801313164.

Adding to 155530031 its reverse (130035551), we get a palindrome (285565582).

The spelling of 155530031 in words is "one hundred fifty-five million, five hundred thirty thousand, thirty-one".