155137561 has 2 divisors, whose sum is σ = 155137562. Its totient is φ = 155137560.

The previous prime is 155137537. The next prime is 155137573. The reversal of 155137561 is 165731551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 124545600 + 30591961 = 11160^2 + 5531^2 .

It is a cyclic number.

It is not a de Polignac number, because 155137561 - 2⁹ = 155137049 is a prime.

It is not a weakly prime, because it can be changed into another prime (155137061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77568780 + 77568781.

It is an arithmetic number, because the mean of its divisors is an integer number (77568781).

Almost surely, 2^155137561 is an apocalyptic number.

It is an amenable number.

155137561 is a deficient number, since it is larger than the sum of its proper divisors (1).

155137561 is an equidigital number, since it uses as much as digits as its factorization.

155137561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 15750, while the sum is 34.

The square root of 155137561 is about 12455.4229554841. The cubic root of 155137561 is about 537.3273991327.

The spelling of 155137561 in words is "one hundred fifty-five million, one hundred thirty-seven thousand, five hundred sixty-one".