155440613 has 2 divisors, whose sum is σ = 155440614. Its totient is φ = 155440612.

The previous prime is 155440567. The next prime is 155440631. The reversal of 155440613 is 316044551.

It is a happy number.

Together with next prime (155440631) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 155326369 + 114244 = 12463^2 + 338^2 .

It is a cyclic number.

It is not a de Polignac number, because 155440613 - 2¹⁴ = 155424229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (155445613) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77720306 + 77720307.

It is an arithmetic number, because the mean of its divisors is an integer number (77720307).

Almost surely, 2^155440613 is an apocalyptic number.

It is an amenable number.

155440613 is a deficient number, since it is larger than the sum of its proper divisors (1).

155440613 is an equidigital number, since it uses as much as digits as its factorization.

155440613 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7200, while the sum is 29.

The square root of 155440613 is about 12467.5824841867. The cubic root of 155440613 is about 537.6770505975.

The spelling of 155440613 in words is "one hundred fifty-five million, four hundred forty thousand, six hundred thirteen".