155087281 has 2 divisors, whose sum is σ = 155087282. Its totient is φ = 155087280.

The previous prime is 155087249. The next prime is 155087293. The reversal of 155087281 is 182780551.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 95550625 + 59536656 = 9775^2 + 7716^2 .

It is a cyclic number.

It is not a de Polignac number, because 155087281 - 2⁵ = 155087249 is a prime.

It is a super-2 number, since 2×155087281² = 48104129455945922, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 155087281.

It is not a weakly prime, because it can be changed into another prime (155087201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 77543640 + 77543641.

It is an arithmetic number, because the mean of its divisors is an integer number (77543641).

Almost surely, 2^155087281 is an apocalyptic number.

It is an amenable number.

155087281 is a deficient number, since it is larger than the sum of its proper divisors (1).

155087281 is an equidigital number, since it uses as much as digits as its factorization.

155087281 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 22400, while the sum is 37.

The square root of 155087281 is about 12453.4043939800. The cubic root of 155087281 is about 537.2693436868.

It can be divided in two parts, 1550 and 87281, that added together give a triangular number (88831 = T₄₂₁).

The spelling of 155087281 in words is "one hundred fifty-five million, eighty-seven thousand, two hundred eighty-one".