155816197 has 2 divisors, whose sum is σ = 155816198. Its totient is φ = 155816196.

The previous prime is 155816189. The next prime is 155816201. The reversal of 155816197 is 791618551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 149670756 + 6145441 = 12234^2 + 2479^2 .

It is a cyclic number.

It is not a de Polignac number, because 155816197 - 2³ = 155816189 is a prime.

It is equal to p_8752867 and since 155816197 and 8752867 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (155816107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77908098 + 77908099.

It is an arithmetic number, because the mean of its divisors is an integer number (77908099).

Almost surely, 2^155816197 is an apocalyptic number.

It is an amenable number.

155816197 is a deficient number, since it is larger than the sum of its proper divisors (1).

155816197 is an equidigital number, since it uses as much as digits as its factorization.

155816197 is an evil number, because the sum of its binary digits is even.

The product of its digits is 75600, while the sum is 43.

The square root of 155816197 is about 12482.6358194093. The cubic root of 155816197 is about 538.1097570462.

The spelling of 155816197 in words is "one hundred fifty-five million, eight hundred sixteen thousand, one hundred ninety-seven".