155545931 has 2 divisors, whose sum is σ = 155545932. Its totient is φ = 155545930.

The previous prime is 155545919. The next prime is 155545961. The reversal of 155545931 is 139545551.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (139545551) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-155545931 is a prime.

It is a super-2 number, since 2×155545931² = 48389073301313522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (155545961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77772965 + 77772966.

It is an arithmetic number, because the mean of its divisors is an integer number (77772966).

Almost surely, 2^155545931 is an apocalyptic number.

155545931 is a deficient number, since it is larger than the sum of its proper divisors (1).

155545931 is an equidigital number, since it uses as much as digits as its factorization.

155545931 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 67500, while the sum is 38.

The square root of 155545931 is about 12471.8054426775. The cubic root of 155545931 is about 537.7984566363.

The spelling of 155545931 in words is "one hundred fifty-five million, five hundred forty-five thousand, nine hundred thirty-one".